V^A^XV/VJL  J*.J**Jl_/\f/Uj%L ji  Y 


LIBRARY 

OF   THE 

UNIVERSITY  OF  CALIFORNIA. 


Class 


)ks,  except  those  reserved  for  special  ref- 
erence use,  may  be  kept  for  one  week  and  once 
le  time.     This  book  is  due  to 
T.     A 

it  is  kept  overtime. 


li 


OCT  2  T  1915 


1  4 
FE-B  -  1  1916 


FRONTISPIECE. — A  Shade  Plant,  Jack-in-the-Pulpit 


FOUNDATIONS  OF  BOTANY 


BY 

JOSEPH  Y.  BERGEN,  A.M. 

INSTRUCTOR  IN  BIOLOGY,  ENGLISH  HIGH  SCHOOL,  BOSTON 


BOSTON,  U.S.A. 

GINN   &   COMPANY,  PUBLISHERS 
tbcmTtim  |)re00 
1904 


COPYRIGHT,  1901,  BY 
JOSEPH    Y.   BERGEN 

ALL  BIGHTS  RESERVED 


PREFACE 

THIS  book  is  written  upon  the  same  plan  as  the  author's 
Elements  of  Botany.  A  few  chapters  stand  here  but  little 
altered  from  the  former  work,  but  most  of  them  have  been 
rewritten  and  considerably  enlarged,  and  many  new  ones 
have  been  added.  The  principal  changes  in  the  book  as  a 
whole  are  these  : 

1.  Most  of  the  discussion  of  ecological  topics  is  put  by 
itself,  in  Part  II. 

2.  The  amount  of  laboratory  work  on  the   anatomy  and 
physiology  of  seed-plants  is  considerably  increased  and  addi- 
tional experiments  are  introduced. 

3.  The  treatment  of  spore-plants  is  greatly  extended,  so  as 
to  include  laboratory  work  on  the  most  important  groups. 

4.  The  meagre  Flora  which  accompanied  the  earlier  book 
has  been  replaced  by  one  which  contains  fairly  full  descrip- 
tions of  nearly  seven  hundred  species  of  plants.      Most  of 
these  are  wild,  but  a  considerable  number  of  cultivated  species 
have  been  included,  mainly  for  the  convenience  of  schools  in 
large  cities. 

Ample  material  is  offered  for  a  year's  course,  four  or  five 
periods  per  week.  The  author  is  well  aware  that  most  schools 
devote  but  half  a  year  to  botany,  but  the  tendency  sets  strongly 
toward  allowing  more  time  for  this  subject.  Even  in  schools 
where  the  minimum  time  allowance  is  devoted  to  botany,  there 
is  a  distinct  advantage  in  being  provided  with  a  book  which 
allows  the  teacher  considerable  option  as  regards  the  kind 
and  amount  of  work  which  he  shall  offer  to  his  classes. 

iii 


IV  PREFACE 

Suggestions  are  made  in  the  teacher's  Handbook,  which 
accompanies  this  volume,  in  regard  to  shaping  half-year 
courses. 

The  latest  authorities  in  the  various  departments  of  botany 
have  been  consulted  on  all  doubtful  points,  and  the  attempt 
has  been  to  make  the  book  scientifically  accurate  throughout, 
yet  not  unduly  difficult. 

Most  of  the  illustrations  have  been  redrawn  from  those  in 
standard  German  works  of  an  advanced  character,  or  drawn 
from  nature  or  from  photographs,  expressly  for  this  book. 
Besides  the  sources  of  drawings  acknowledged  in  the  author's 
Elements,  many  cuts  have  been  taken  from  the  botanies  of 
Frank,  Prantl,  Detmer,  Murray,  and  Bennett  and  Murray,  as 
well  as  from  Schiinper's  Pflanzengeographie. 

Of  the  drawings  from  nature  or  from  photographs,  some 
figures,  and  Plates"  I,  VII,  and  VIII,  are  by  Mr.  Edmund 
Garrett  of  Boston  ;  several  figures,  the  Frontispiece,  and 
Plates  II,  IV,  X,  XI,  are  by  Mr.  Bruce  Horsfall  of  New  York  ; 
several  figures  are  by  Mr.  F.  Schuyler  Mathews  of  Boston ;  a 
large  number  of  figures  and  Plate  V  are  by  Mr.  E.  N.  Fischer 
of  Boston;  several  figures  are  by  Mr.  E.  E.  Kingsbury  of  Boston 
and  Dr.  J.  W.  Folsom  of  the  University  of  Illinois. 

Thanks  for  the  use  of  photographs  are  due  to  Mr.  H.  G. 
Peabody  of  Boston  (Fig.  234),  to  Mr.  J.  H.  White  of  Boston 
(Figs.  32,  75,  222),  to  Professor  Conway  MacMillan  of  the  Uni- 
versity of  Minnesota  (Frontispiece),  and  to  Professor  F.  V. 
Coville  of  Washington  (Plate  VII).  Figs.  28  and  275  are 
taken  by  permission  from  the  Primer  of  Forestry,  issued  by  the 
Division  of  Forestry,  U.  S.  Department  of  Agriculture.  Figs. 
263,  264,  276  are  copied  by  permission  from  Professor  W.  J. 
BeaPs  Seed  Dispersal,  and  Figs.  226,  229,  233  from  Professor 
W.  M.  Davis's  Physical  Geography.  Fig.  269  is  from  a  photo- 
graph by  Professor  C.  F.  Millspaugh  of  Chicago.  Plate  IV 
is  from  a  photograph  by  Dr.  H.  J.  Webber. 


PREFACE  V 

Most  of  the  redrawn  illustrations  (not  microscopical)  from 
various  European  sources  are  by  Mr.  Fischer.  Most  of  the 
microscopical  ones  (and  a  number  of  figures  from  nature)  are 
by  Dr.  J.  W.  Folsom  of  the  University  of  Illinois,  and  many 
of  both  classes  are  by  Mr.  Mathews.  Thanks  are  due  to 
Professor  J.  M.  Holzinger  of  the  Winona  (Minn.)  State 
Normal  School,  to  Professor  L.  Murbach  of  the  Detroit  High 
School,  and  to  Mr.  I.  S.  Cutter  of  Lincoln,  Nebraska,  for 
their  many  discriminating  criticisms  of  the  proof  of  Parts  I 
and  II.  Mr.  Samuel  F.  Tower  of  the  Boston  English  High 
School,  Professor  Charles  V.  Piper  of  the  Washington  State 
Agricultural  College,  and  Dr.  Kodney  H.  True,  Lecturer  on 
Botany  at  Harvard  University,  have  all  read  the  whole  or 
large  portions  of  Part  I  and  given  valuable  suggestions. 
Professor  W.  F.  Ganong,  of  Smith  College,  has  read  and 
criticised  Part  II. 

The  chapters  on  spore-plants,  excepting  a  small  amount  of 
matter  retained  from  the  Elements  of  Botany,  are  entirely  the 
work  of  Mr.  A.  B.  Seymour  of  the  Cryptogamic  Herbarium  of 
Harvard  University. 

The  author  has  attempted  to  steer  a  middle  course  between 
the  advocates  of  the  out-of-door  school  and  of  the  histological 
school  of  botany  teaching.  He  has  endeavored  never  to  use  a 
technical  term  where  he  could  dispense  with  it,  and  on  the 
other  hand,  not  to  become  inexact  by  shunning  necessary 
terms.  In  deciding  questions  of  this  sort,  a  priori  reasoning 
is  of  little  value  ;  one  must  ascertain  by  repeated  trials  how 
much  of  a  technical  vocabulary  the  average  beginner  in  botany 
can  profitably  master.  The  teacher  who  has  discovered  that 
not  one  of  the  boys  in  a  division  of  thirty-six  pupils  knows 
that  his  own  desk-top  is  of  cherry  wood  may  well  hesitate 
about  beginning  his  botany  teaching  with  a  discourse  on  cen- 
trospheres  and  karyokinesis.  It  has  been  assumed  throughout 
this  book  that,  other  things  being  equal,  the  knowledge  is  of 


VI  PREFACE 

most  worth  which,  touches  the  pupil's  daily  life  at  the  most 
points,  and  therefore  best  enables  him  to  understand  his  own 
environment.  On  the  other  hand,  the  author  has  no  sympathy 
with  those  who  decry  the  use  of  apparatus  in  botany  teaching 
in  secondary  schools  and  who  would  confine  the  work  of  their 
pupils  mainly  within  the  limits  of  what  can  be  seen  with  the 
unaided  eye.  If  the  compound  microscope  plainly  reveals 
things  shown  only  imperfectly  by  a  magnifier  and  not  seen  at 
all  with  the  naked  eye,  —  use  the  microscope  !  If  iodine 
solution  or  other  easily  prepared  reagents  make  evident  the 
existence  of  structures  or  substances  not  to  be  detected  with- 
out them,  —  then  use  the  reagents  !  No  one  thinks  of  deny- 
ing a  boy  the  use  of  a  spyglass  or  a  compass  for  his  tr.amps 
afield  or  his  outings  in  a  boat  because  he  has  not  studied 
physics.  No  one  would  refuse  to  let  an  intelligent  boy  or 
girl  use  a  camera  because  the  would-be  photographer  had  not 
mastered  the  chemical  reactions  that  follow  upon  the  expo- 
sure of  a  sensitized  plate.  Yet  it  is  equally  illogical  to  defer 
some  of  the  most  fascinating  portions  of  botanical  study  until 
the  college  course,  to  which  most  never  attain.  When  the 
university  professor  tells  the  teacher  that  he  ought  not  to 
employ  the  ordinary  appliances  of  elementary  biological  inves- 
tigation in  the  school  laboratory  because  the  pupils  cannot 
intelligently  use  them,  the  teacher  is  forced  to  reply  that  the 
professor  himself  cannot  intelligently  discuss  a  subject  of 
which  he  has  no  personal  knowledge.  The  pupils  are  deeply 
interested;  they  prove  by  their  drawings  and  their  recita- 
tions that  they  have  seen  a  good  way  into  plant  structures 
and  plant  functions  ;  then  why  not  let  them  study  botany 
in  earnest  ? 

J.  Y.  B. 

CAMBRIDGE,  January,  1901. 


CONTENTS 


PART  I 

STRUCTURE,  FUNCTIONS,  AND  CLASSIFICATION  OF  PLANTS 

CHAPTER  I 

PAGES 

THE  SEED  AND  ITS  GERMINATION       ......         6-13 

CHAPTER  II 
STORAGE  OF  FOOD  IN  THE  SEED         .         .         .         .         .         .       14-24 

CHAPTER  III 
MOVEMENTS,  DEVELOPMENT,  AND  MORPHOLOGY  OF  THE  SEEDLING       25-35 

CHAPTER  IV 
ROOTS 36-61 

CHAPTER  V 
STEMS 62-82 

CHAPTER  VI 
STRUCTURE  OF  THE  STEM   ........     83-103 

CHAPTER  VII 
LIVING  PARTS  OF  THE  STEM;   WORK  OF  THE  STEM  .         .         .  104-118 

CHAPTER  VIII 
BUDS 119-129 

vii 


Vlll  CONTENTS 

CHAPTER  IX  pAGEg 

LEAVES        130-139 

CHAPTER  X 

LEAF- ARRANGEMENT  FOR  EXPOSURE  TO  SUN  AND  AIR;    MOVE- 
MENTS OF  LEAVES  AND  SHOOTS    .  ...  140-149 

CHAPTER  XI 
MINUTE  STRUCTURE  OF  LEAVES  ;   FUNCTIONS  OF  LEAVES  .         .   150-177 

CHAPTER  XII 
PROTOPLASM  AND  ITS  PROPERTIES       ......   178-185 

CHAPTER  XIII 
INFLORESCENCE,  OR  ARRANGEMENT  OF  FLOWERS  ON  THE  STEM  186-191 

CHAPTER  XIV 
THE  STUDY  OF  TYPICAL  FLOWERS 192-196 

CHAPTER  XV 
PLAN  AND  STRUCTURE  OF  THE  FLOWER  AND  ITS  ORGANS  .   197-207 

CHAPTER  XVI 

TRUE  NATURE  OF  FLORAL  ORGANS  ;  DETAILS  OF  THEIR  STRUC- 
TURE ;  FERTILIZATION  ........  208-216 

CHAPTER  XVII 
THE  STUDY  OF  TYPICAL  FRUITS 217-220 

CHAPTER  XVIII 
THE  FRUIT .  221-227 

CHAPTER  XIX 
THE  CLASSIFICATION  OF  PLANTS 228-234 


CONTENTS 


IX 


CHAPTER  XX 
TYPES  OF  CRYPTOGAMS  ;   THALLOPHYTES    . 

CHAPTER  XXI 
TYPES  OF  CRYPTOGAMS  ;   BRYOPHYTES 

CHAPTER  XXII 
TYPES  OF  CRYPTOGAMS  ;   PTERIDOPHYTES  . 

CHAPTER  XXIII 
THE  EVOLUTIONARY   HISTORY  OF  PLANTS  . 


PAGES 

.  235-276 


.  277-285 


.  286-297 


.  298-305 


PART  II 


ECOLOGY,  OR  RELATIONS  OF  PLANTS  TO  THE  WORLD 
ABOUT  THEM 

CHAPTER  XXIV 
PLANT  SOCIETIES .  307-322 


CHAPTER  XXV 


BOTANICAL  GEOGRAPHY 


324-33$ 


CHAPTER  XXVI 
PARASITES,  ENSLAVED  PLANTS,  MESSMATES,  CARNIVOROUS  PLANTS  336-344 

CHAPTER  XXVII 
How  PLANTS  PROTECT  THEMSELVES  FROM  ANIMALS  .  345-352 


X  CONTENTS 

CHAPTER  XXVIII 

PAGES 

ECOLOGY  OP  FLOWERS         ........  353-372 

CHAPTER  XXIX 
How  PLANTS  ARE  SCATTERED  AND  PROPAGATKD        .         .         .  373-386 

CHAPTER  XXX 

THE    STRUGGLE    FOR   EXISTENCE   AND   THE   SURVIVAL   OF   THE 

FITTEST         .  387-395 


LIST    OF   PLATES 

FRONTISPIECE.    Jack-in-the-pulpit,  a  typical  shade-plant,  with  large, 

thin  leaves. 

Facing  page 

PLATE  I.  Sand-dunes  with  sea  rye  grass.  Deep-rooted,  with  exten- 
sively running  rootstocks 76 

PLATE  II.     Pollarded  willows,  showing  growth  of  slender  twigs  from 

adventitious  buds 128 

PLATE  III.  Japanese  ivy,  a  tendril-climber  growing  on  face  of  a 
building,  showing  leaves  all  exposed  to  sunlight  at  the  most 
advantageous  angle 140 

PLATE  IV.  Cypress  swamp,  showing  "  Spanish  moss "  (Tillandsia), 
a  phanerogamic  epiphyte  practically  leafless,  the  work  ordinarily 
done  by  leaves  devolving  on  the  slender  stems.  The  cypress 
trees  are  furnished  with  "  knees  "  or  projections  from  the  roots, 
which  are  thought  by  some  to  absorb  air  .  .  .  .  .158 

PLATE  V.     Indian  pipe,  a  saprophytic  seed-plant,  wholly  destitute 

of  chlorophyll  and  with  scales  instead  of  foliage  leaves        .         .  168 

PLATE  VI.  Fan  palms,  showing  general  habit  of  the  tree,  and  large 
projecting  bases  of  old  petioles  left  after  the  decay  of  the  leaves  176 

PLATE  VII.     A  tree  yucca  in  the  Mohave  Desert,  a  characteristic 

xerophytic  tree.     Other  sparse  desert  vegetation  is  also  shown  .  316 

PLATE  VIII.  Belt  of  trees  along  a  Nebraskan  river,  showing  depend- 
ence of  forest  on  water  supply  .......  334 

PLATE  IX.  Cottonwood.  Tree  largely  overgrown  with  American 
mistletoe,  near  Mesilla,  New  Mexico.  The  photograph  was  taken 
in  winter,  when  the  tree  was  leafless,  so  that  all  the  foliage  shown 
is  that  of  the  mistletoe 336 

PLATE  X.  Humming-bird  visiting  flowers  of  the  trumpet  creeper. 
This  is  one  of  the  best  North  American  examples  of  a  flower 
mainly  pollinated  by  birds 362 

PLATE  XI.  Asters  and  golden-rods,  Composite,  illustrating  the 
principle  of  grouping  many  small  flowers  into  heads  (and  in 
the  golden-rod  the  heads  into  rather  close  clusters)  to  facilitate 
the  visits  of  insects  .  .  372 


FOUNDATIONS  OF  BOTANY 


INTRODUCTION 

"  Botany  is  the  science  which  endeavors  to  answer  every  reason- 
able question  about  plants."  l 

THE  plant  is  a  living  being,  provided  generally  with 
many  parts,  called  organs,  which  it  uses  for  taking  in  nour- 
ishment, for  breathing,  for  protection  against  its  enemies, 
and  for  reproducing  itself  and  so  keeping  up  the  numbers 
of  its  own  kind.  The  study  of  the  individual  plant  there- 
fore embraces  a  variety  of  topics,  and  the  examination  of 
its  relation  to  others  introduces  many  more  subjects. 

Morphology,  or  the  science  of  form,  structure,  and  so  on, 
deals  with  the  plant  without  much  regard  to  its  character 
as  a  living  thing.  Under  this  head  are  studied  the  forms 
of  plants  and  the  various  shapes  or  disguises  which  the 
same  sort  of  organ  may  take  in  different  kinds  of  plants, 
their  gross  structure,  their  microscopical  structure,  their 
classification,  and  the  successive  stages  in  the  develop- 
ment of  the  individual  plant. 

Plant  Physiology  treats  of  the  plant  in  action,  how  it  lives, 
breathes,  feeds,  grows,  and  produces  others  like  itself. 

Geographical  Distribution,  or  botanical  geography,  dis- 
cusses the  range  of  the  various  kinds  of  plants  over  the 

1  Professor  George  L.  Goodale. 
1 


2  FOUNDATIONS   OF   BOTANY 

earth's  surface.  Another  subdivision  of  botany,  usually 
studied  along  with  geology,  describes  the  history  of  plant 
life  on  the  earth  from  the  appearance  of  the  first  plants 
until  the  present  time. 

Systematic  Botany,  or  the  classification  of  plants,  should 
naturally  follow  the  examination  of  the  groups  of  seed- 
plants  and  spore-plants. 

Plant  Ecology  treats  of  the  relations  of  the  plant  to 
the  conditions  under  which  it  lives.  Under  this  division 
of  the  science  are  studied  the  effects  of  soil,  climate,  and 
friendly  or  hostile  animals  and  plants  on  the  external 
form,  the  internal  structure,  and  the  habits  of  plants. 
This  is  in  many  respects  the  most  interesting  department 
of  botany,  but  it  has  to  be  studied  for  the  most  part  out 
of  doors. 

Many  of  the  topics  suggested  in  the  above  outline  cannot 
well  be  studied  in  the  high  school.  There  is  not  usually 
time  to  take  up  more  than  the  merest  outline  of  botanical 
geography,  or  to  do  much  more  than  mention  the  impor- 
tant subject  of  Economic  Botany  —  the  study  of  the  uses 
of  plants  to  man.  It  ought,  however,  to  be  possible  for 
the  student  to  learn  in  his  high-school  course  a  good  deal 
about  the  simpler  facts  of  morphology  and  of  vegetable 
physiology.  One  does  not  become  a  botanist  —  not  even 
much  of  an  amateur  in  the  subject  —  by  reading  books 
about  botany.  It  is  necessary  to  study  plants  themselves, 
to  take  them  to  pieces  and  make  out  the  connection  of  their 
parts,  to  examine  with  the  microscope  small  portions  of  the 
exterior  surface  and  thin  slices  of  all  the  variously  built 
materials  or  tissues  of  which  the  plant  consists.  All  this 
can  be  done  with  living  specimens  or  with  those  taken 


INTRODUCTION 

from  dead  parts  of  plants  that  have  been  preserved  in  any 
suitable  way,  as  by  drying  or  by  placing  in  alcohol  or  other 
fluids  which  prevent  decay.  Living  plants  must  be  studied 
in  order  to  ascertain  what  kinds  of  food  they  take,  what 
kinds  of  waste  substances  they  excrete,  how  and  where 
their  growth  takes  place  and  what  circumstances  favor  it, 
how  they  move,  and  indeed  to  get  as  complete  an  idea  as 
possible  of  what  has  been  called  the  behavior  of  plants. 

Since  the  most  familiar  and  most  interesting  plants 
spring  from  seeds,  the  beginner  in  botany  can  hardly  do 
better  than  to  examine  at  the  outset  the  structure  of  a  few 
familiar  seeds,  then  sprout  them  and  watch  the  growth  of 
the  seedlings  which  spring  from  them.  Afterwards  he 
may  study  in  a  few  typical  examples  the  organs,  structure, 
and  functions  of  seed-plants,  trace  their  life  history,  and 
so,  step  by  step,  follow  the  process  by  which  a  new  crop 
of  seeds  at  last  results  from  the  growth  and  development 
of  such  a  seed  as  that  with  which  he  began.  • 

After  he  has  come  to  know  in  a  general  way  about  the 
structure  and  functions  of  seed-plants,  the  student  may 
become  acquainted  with  some  typical  cryptogams  or  spore- 
plants.  There  are  so  many  groups  of  these  that  only  a 
few  representative  ones  can  be  chosen  for  study. ' 


PART  I 

STRUCTURE,    FUNCTIONS,   AND    CLASSIFI- 
CATION  OF   PLANTS 

CHAPTER   I 
THE    SEED   AND   ITS   GERMINATION 

1,  Germination  of  the  Squash  Seed.  —  Soak  some  squash  seeds  in 
tepid  water  for  twelve  hours  or  more.  Plant  these  about  an  inch 
deep  in  damp  sand  or  pine  sawdust  or  peat-moss  in  a  wooden  box 
which  has  had  holes  enough  bored  through  the  bottom  so  that  it  will 
not  hold  water.  Put  the  box  in  a  warm  place  (not  at  any  time  over 
70°  or  80°  Fahrenheit),1  and  cover  it  loosely  with  a  board  or  a  pane 
of  glass.  Keep  the  sand  or  sawdust  moist,  but  not  wet,  and  the 
seeds  will  germinate.  As  soon  as  any  of  the  seeds,  on  being  dug  up, 
are  found  to  have  burst  open,  sketch  one  in  this  condition,2  noting 
the  manner  in  which  the  outer  seed-coat  is  split,  and  continue  to 
examine  the  seedlings  at  intervals  of  two  days,  until  at  least  eight 
stages  in  the  growth  of  the  plantlet  have  been  noted.8 

1  Here  aud  elsewhere  throughout  the  book  temperatures  are  expressed  iu 
Fahrenheit  degrees,  since  with  us,  unfortunately,  the  Centigrade  scale  is  not 
the  familiar  one,  outside  of  physical  and  chemical  laboratories. 

2  The  student  need  not  feel  that  he  is  expected  to  make  finished  drawings 
to  record  what  he  sees,  but  some  kind  of  careful  sketch,  if  only  the  merest 
outline,  is  indispensable.     Practice  and  study  of  the  illustrations  hereafter 
given  will  soon  impart  some  facility  even  to  those  who  have  had  little  or  r.o 
instruction  in  drawing.     Consult  here  Figs.  9  and  89. 

8  The  class  is  not  to  wait  for  the  completion  of  this  work  (which  may,  if 
desirable,  be  done  by  each  pupil  at  home),  but  is  to  proceed  at  once  with  the 
examination  of  the  squash  seed  and  of  other  seeds,  as  directed  in  the  follow- 
ing sections,  and  to  set  some  beans,  peas,  and  corn  to  sprouting,  so  that  they 
may  be  studied  at  the  same  time  with  the  germinating  squashes. 

5 


FOUNDATIONS   OF  BOTANY 


— e 


cot. 


Observe  particularly  how  the  sand  is  pushed  aside  by  the  rise  of 
the  young  seedlings.  Suggest  some  reason  for  the  manner  in  which 
the  sand  is  penetrated  by  the  rising  stem. 

2.  Examination  of  the  Squash  Seed. — 
Make  a  sketch  of  the  dry  seed,  natural  size. 
Note  the  little  scar  at  the  pointed  end  of  the 
seed  where  the  latter  was  attached  to  its 
place  of  growth  in  the  squash.  Label  this 
liilum. 

Note  the  little  hole  in  the  hilum  ;  it  is 
the  micropyle,  seen  most  plainly  in  a  soaked 
seed.  (If  there  are  two  depressions  on  the 
hilum  the  deeper  one  is  the  micropyle.) 

Describe  the  color  and  texture  of  the  outer 
coating  of  the  seed.  With  a  scalpel  or  a  very 
sharp  knife  cut  across  near  the  middle  a  seed 
that  has  been  soaked  in  water  for  twenty- 
four  hours.  Squeeze  one  of  the  portions, 
held  edgewise  between  the  thumb  and  finger, 
in  such  a  way  as  to  separate  slightly  the 
halves  into  which  the  contents  of  the  seed  is 
naturally  divided.  Examine  with  the  mag- 
nifying glass  the  section  thus  treated,  make 
a  sketch  of  it,  and  label  the  shell  or  covering 
of  the  seed  and  the  kernel  within  this. 

Taking  another  soaked  seed,  chip  away 
the  white  outer  shell,  called  the  testa,  and 
observe  the  thin,  greenish  inner  skin  (Fig. 
1,'e),  with  which  the  kernel  of  the  seed  is 
closely  covered.1 

Strip  this  off  and  sketch  the  uncovered  ker- 
nel or  embryo.  Note  that  at  one  end  it  tapers 
to  a  point.  This  pointed  portion,  known 
as  the  Jiypocotyl,  will  develop  after  the  seed 
sprouts  into  the  stem  of  the  plantlet,  like  that  shown  at  c  in  Fig.  2. 
Split  the  halves  of  the  kernel  entirely  apart  from  each  other, 

i  See  footnote  2  to  Sect.  18. 


C 


FIG.  1. — Lengthwise  Section 
of  a  Squash  Seed.  (Magni- 
fied about  five  times.) 


THE    SEED   AND   ITS   GERMINATION 


noticing  that  they  are  only  attached  for  a  very  little  way  next  to 
the  hypocotyl,  and  observe  the  thickness  of  the  halves  and  the  slight 
unevenness  of  the  inner  surfaces.  These  halves  are  called  seed-leaves 
or  cotyledons. 

Have  ready  some  seeds  which  have  been  soaked  for  twenty-four 
hours  and  then  left  in  a  loosely  covered  jar  on  damp  blotting  paper 
at  a  temperature  of  70°  or  over 
until  they  have  begun  to  sprout. 

Split  one  of  these  seeds  apart, 
separating  the  cotyledons,  and 
observe,  at  the  junction  of  these, 
two  very  slender  pointed  objects, 
the  rudimentary  leaves  of  the 
plumule  or  first  bud  (Fig.  1,  p). 

3.  Examination  of  the  Bean*. 
—  Study  the  seed,  both  dry  and 
after  twelve  hours'  soaking,  in 
the  same  general  way  in  which 
the  squash  seed  has  just  been 
examined.1 

Notice  the  presence  of  a  dis- 
tinct plumule,  consisting  of  a  pair 
of  rudimentary  leaves  between 
the  cotyledons,  just  where  they 
are  joined  to  the  top  of  the  hypo- 
cotyl. In  many  seeds  (as  the  pea) 
the  plumule  does  not  show  dis- 
tinct  leaves.  But  in  all  cases 
the  plumule  contains  the  growing 
point,  the  tip  of  the  stem  from 
which  all  the  upward  growth  of 
the  plant  is  to  proceed. 

Make  a  sketch  of  these  leaves  as  they  lie  in  place  on  one  of  the 
cotyledons,  after  the  bean  has  been  split  open. 

1  The  larger  the  variety  of  bean  chosen,  the  easier  it  will  be  to  see  and 
sketch  the  several  parts.  The  large  red  kidney  bean,  the  horticultural  bean, 
or  the  lima  bean  will  do  well  for  this  examination. 


FIG.  2.  — The  Castor  Bean  and  its 
Germination. 

A,  longitudinal  section  of  ripe  seed  ;  t, 
testa ;  co,  cotyledon  ;  c,  hypocotyl ; 
B,  sprouting  seed  covered  with  endo- 
sperm ;  (7,  same,  with  half  of  endo- 
sperm removed ;  D,  seedling ;  r,  pri- 
mary root ;  r',  secondary  roots ;  c,  arch 
of  hypocotyl. 


8  FOUNDATIONS   OF   BOTANY 

Note  the  cavity  in  each  cotyledon  caused  by  the  pressure  of  the 
plumule  and  of  the  hypocotyl. 

4,  Examination  of  the  Pea.  — There  are  no  very  important  points 
of  difference  between  the  bean  and  pea,  so  far  as  the  structure  of 
the  seed  is  concerned,  but  the  student  should  rapidly  dissect  a  few 
soaked  peas  to  get  an  idea  of  the  appearance  of  the  parts,  since  he 
is  to  study  the  germination  of  peas  in  some  detail. 

Make  only  one  sketch,  that  of  the  hypocotyl  as  seen  in  position 
after  the  removal  of  the  seed-coats.1 

5.  Germination  of  the  Bean  or  the  White  Lupine,  the  Pea,  and  the 
Grain  of  Corn.  —  Soak  some  beans  or   lupine  seeds  as  directed  in 
Section  3,  plant  them,2  and  make  a  series  of  sketches  on  the  same 
general  plan  as  those  in  Fig.  9. 

Follow  the  same  directions  with  some  peas  and  some  corn.  In  the 
case  of  the  corn,  make  six  or  more  sketches  at  various  stages  to  illus- 
trate the  growth  of  the  plumule  and  the  formation  of  roots ;  first  a 
main  root  from  the  base  of  the  hypocotyl,  then  others  more  slender 
from  the  same  region,  and  later  on  still  others  from  points  higher 
up  on  the  stem  (see  Fig.  15).  The  student  may  be  able  to  dis- 
cover what  becomes  of  the  large  outer  part  of  the  embryo.  This  is 
really  the  single  cotyledon  of  the  corn  (Fig.  6).  It  does  not  as  a 
whole  rise  above  ground,  but  most  of  it  remains  in  the  buried  grain, 
and  acts  as  a  digesting  and  absorbing  organ  through  which  the 
endosperm  or  food  stored  outside  of  the  embryo  is  transferred  into 
the  growing  plant,  as  fast  as  it  can  be  made  liquid  for  that  purpose. 

6,  Germination  of  the  Horse-Chestnut .  —  Plant  some  seeds  of  the 
horse-chestnut  or  the  buckeye,  study  their  mode  of  germination,  and 
observe  the  nature  and  peculiar  modifications  of  the  parts. 

Consult_Gray's  Structural  Botany,  Vol.  I,  pp.  19,  20. 

7.  Conditions  Requisite  for   Germination. -- When   we 
try  to  enumerate  the  external  conditions  which  can  affect 

1  The  teacher  will  find  excellent  sketches  of  most  of  the  germinating  seeds 
described  in  the  present  chapter  in  Miss  Newell's  Outlines  of  Lessons  in 
Botany,  Part  I. 

2  The  pupil  may  economize  space  by  planting  the  new  seeds  in  boxes 
from  -which  part  of  the  earlier  planted  seeds  have  been  dug  up  for  use  in 
sketching,  etc. 


THE    SEED   AND    ITS   GERMINATION  9 

germination,  we  find  that  the  principal  ones  are  heat, 
moisture,  and  presence  of  air.  A  few  simple  experiments 
will  show  what  influence  these  conditions  exert. 

8.  Temperature.  —  Common  observation  shows  that  a 
moderate  amount  of  warmth  is  necessary  for  the  sprout- 
ing of  seeds.  Every  farmer  or  gardener  knows  that 
during  a  cold  spring  many  seeds,  if  planted,  will  rot  in 
the  ground.  But  a  somewhat  exact  experiment  is  neces- 
sary to  show  what  is  the  best  temperature  for  seeds  to 
grow  in,  and  whether  variations  in  the  temperature  make 
more  difference  in  the  quickness  with  which  they  begin 
to  germinate  or  in  the  total  per  cent  which  finally  succeed. 

EXPERIMENT   I 

Relation  of  Temperature  to  Germination.  —  Prepare  at  least  four 
teacups  or  tumblers,  each  with  wet  soft  paper  packed  in  the  bottom 
to  a  depth  of  nearly  an  inch.  Have  a  tightly  fitting  cover  over  each. 
Put  in  each  vessel  the  same  number  of  soaked  peas.  Stand  the  ves- 
sels with  their  contents  in  places  where  they  will  be  exposed  to  dif- 
ferent, but  fairly  constant,  temperatures,  and  observe  the  several 
temperatures  carefully  with  a  thermometer.  Take  pains  to  keep  the 
tumblers  in  the  warm  places  from  drying  out,  so  that  their  contents 
will  not  be  less  moist  than  that  of  the  others.  The  following  series 
is  merely  suggested,  —  other  values  may  be  found  more  convenient. 
Note  the  rate  of  germination  in  each  place  and  record  in  tabular 
form  as  follows : 

No.  of  seeds  sprouted  in   24  hrs.    48  hrs.    72  hrs.    96- hrs.    etc. 
At  32°, 
At  50°, 
At  70°, 
At  900,1 

1  For  the  exact  regulation  of  the  temperatures  a  thermostat  (see  Handbook) 
is  desirable.  If  one  is  available,  a  maximum  temperature  of  100°  or  over 
should  be  tried. 


10 


FOUNDATIONS   OF   BOTANY 


9.  Moisture.  —  What  was  said  in  the  preceding  section 
in  regard  to  temperature  applies  also  to  the  question  of 
the  best  conditions  for  germination  as  regards  the  supply 
of  moisture.  The  soil  in  which  seeds  grow  out  of  doors 
is  always  moist;  it  rests  with  the  experimenter  to  find 
out  approximately  what  is  the  best  amount  of  moisture. 

EXPERIMENT   II1 

Relation  of  Water  to  Germination.  —  Arrange  seeds  in  several 
vessels  as  follows : 

In  the  first  put  blotting  paper  that  is  barely  moistened ;  on  this 
put  some  dry  seeds. 

In  the  second  put  blotting  paper  that  has  been  barely  moistened ; 
on  this  put  seeds  that  have  been  soaked  for  twenty-four  hours. 

In  the  third  put 
water  enough  to  soak 
the  paper  thor- 
oughly; use  soaked 
seeds. 

In  the  fourth  put 
water  enough  to  half 
cover  the  seeds. 

Place  the  vessels 
where  they  will  have 
same  temperature  and 
note  the  time  of  ger- 
mination. 

Tabulate  your  re- 
sults as  in  the  previ- 
ous experiment. 

.  10.    Relation  of  the  Air  Supply  to  Germination.  —  If  we 

wish  to  see  how  soaked  seeds  will  behave  with  hardly  any 
air  supply,  it  is  necessary  to  place  them  in  a  bottle  arranged 

1  This  may  be  made  a  home  experiment. 


FlG.  3.  — Soaked  Peas  in  Stoppered  Bottle,  ready 
for  Exhaustion  of  Air. 


THE   SEED  AND   ITS   GERMINATION  11 

as  shown  in  Fig.  3,  exhaust  the  air  by  connecting  the  glass 
tube  with  an  air-pump,  which  is  then  pumped  vigorously, 
and  seal  the  tube  while  the  exhaustion  is  going  on.  The 
sealing  is  best  done  by  holding  a  Bunsen  flame  under  the 
middle  of  the  horizontal  part  of  the  tube.  A  much  easier 
experiment,  which  is  nearly  as  satisfactory,  can,  however, 
be  performed  without  the  air-pump. 

EXPERIMENT   III 

Will  Seeds  Germinate  well  without  a  Good  Supply  of  Air?  — 
Place  some  soaked  seeds  on  damp  blotting  paper  in  the  bottom  of  a 
bottle,  using  seeds  enough  to  fill  it  three-quarters  full,  and  close 
tightly  with  a  rubber  stopper. 

Place  a  few  other  seeds  of  the  same  kind  in  a  second  bottle ; 
cover  loosely. 

Place  the  bottles  side  by  side,  so  that  they  will  have  the  same 
conditions  of  light  and  heat.  Watch  for  results,  and  tabulate  as  in 
previous  experiments. 

Most  seeds  will  not  germinate  under  water,  but  th(j||e  of  the 
sunflower  will  do  so,  and  therefore  Exp.  Ill  may  be  varied  in  the 
following  manner : 

Remove  the  shells  carefully  from  a  considerable  number  of  sun- 
flower seeds.1  Try  to  germinate  one  lot  of  these  in  water  which  has 
been  boiled  in  a  flask  to  remove  the  air,  and  then  cooled  in  the 
same  flask.  Over  the  water,  with  the  seeds  in  it,  a  layer  of  cotton- 
seed oil  about  a  half  inch  deep  is  poured,  to  keep  the  water  from 
contact  with  air.  In  this  bottle  then  there  will  be  only  seeds  and 
air-free  water.  Try  to  germinate  another  lot  of  seeds  in  a  bottle 
half  filled  with  ordinary  water,  also  covered  with  cotton-seed  oil. 
Results? 

11.  Germination  involves  Chemical  Changes. —  If  a  ther- 
mometer is  inserted  into  a  jar  of  sprouting  seeds,  for 

1  These  are  really  fruits,  but  the  distinction  is  not  an  important  one  at 
this  time. 


12  FOUNDATIONS   OF   BOTANY 

instance  peas,  in  a  room  at  the  ordinary  temperature,  the 
peas  will  be  found  to  be  warmer  than  the  surrounding 
air.  This  rise  of  temperature  is  at  least  partly  due  to 
the  absorption  from  the  air  of  that  substance  in  it  which 
supports  the  life  of  animals  and  maintains  the  burning  of 
fires,  namely,  oxygen. 

The  union  of  oxygen  with  substances  with  which  it 
can  combine,  that  is  with  those  which  will  burn,  is  called 
oxidation.  This  kind  of  chemical  change  is  universal  in 
plants  and  animals  while  they  are  in  an  active  condition, 
and  the  energy  which  they  manifest  in  their  growth  and 
movements  is  as  directly  the  result  of  the  oxidation  going 
on  inside  them  as  the  energy  of  a  steam  engine  is  the 
result  of  the  burning  of  coal  or  other  fuel  under  its  boiler. 
In  the  sprouting  seed  much  of  the  energy  produced  by 
the  action  of  oxygen  upon  oxidizable  portions  of  its  con- 
tents is  expended  in  producing  growth,  but  some  of  this 
energy  k  wasted  by  being  transformed  into  heat  which 
escapes  into  the  surrounding  soil.  It  is  this  escaping 
heat  which  is  detected  by  a  thermometer  thrust  into  a 
quantity  of  germinating  seeds. 

EXPERIMENT   IV 

Effect  of  Germinating  Seeds  upon  the  Surrounding  Air.  —  When 
Exp.  Ill  has  been  finished,  remove  a  little  of  the  air  from  above  the 
peas  in  the  first  bottle.  This  can  easily  be  done  with  a  rubber  bulb 
attached  to  a  short  glass  tube.  Then  bubble  this  air  through  some 
clear,  filtered  limewater.  Also  blow  the  breath  through  some  lime- 
water  by  aid  of  a  short  glass  tube.  Explain  any  similarity  in 
results  obtained.  (Carbon  dioxide  turns  limewater  milky.)  After- 
wards insert  into  the  air  above  the  peas  in  the  same  bottle  a  lighted 
pine  splinter,  and  note  the  effect  upon  its  flame. 


THE   SEED   AND   ITS   GERMINATION  13 

12.  Other  Proofs  of  Chemical  Action. —  Besides  the  proof 
of  chemical  changes  in  germinating  seeds  just  described, 
there  are  other  kinds  of  evidence  to  the  same  effect. 

Malt,  which  is  merely  sprouted  barley  with  its  germi- 
nation permanently  stopped  at  the  desired  point  by  the 
application  of  heat,  tastes  differently  from  the  unsprouted 
grain,  and  can  be  shown  by  chemical  tests  to  have  suffered 
a  variety  of  changes.  If  you  can  get  unsprouted  barley 
and  malt,  taste  both  and  see  if  you  can  decide  what  sub- 
stance is  more  abundant  in  the  malt. 

Germinating  kernels  of  corn  undergo  great  alterations 
in  their  structure ;  the  starch  grains  are  gradually  eaten 
away  until  they  are  ragged  and  full  of  holes  and  finally 
disappear. 

13.  The  Embryo  and  its  Development.  —  The  miniature 
plant,  as  it  exists  ready  formed  and  alive  but  inactive  in 
the  seed,  is  called  the  embryo.     In  the  seeds  so  far  ex- 
amined, practically  the  entire  contents  of  the  seed-coats 
consist  of  the  embryo,  but  this  is  not  the  case  with  the 
great  majority  of  seeds,  as  will  be  shown  in  the  following 
chapter. 


CHAPTER   II 


STORAGE   OF   FOOD  IN  THE   SEED 

14.  Food  in  the  Embryo.  —  Squash  seeds  are  not  much 
used  for  human  food,  though  both  these  and  melon  seeds 
are  occasionally  eaten  in  parts  of  Europe ;  but  beans  and 
peas  are  important  articles  of  food.     Whether  the  material 
accumulated  in  the  cotyledons  is  an  aid  to  the  growth  of 
the  young  plant  may  be  learned  from  a  simple  experiment. 

15.  Mutilated  and  Perfect  Seedlings.  —  One  of  the  best 
ways  in  which  to  find  out  the  importance  and  the  special 

use  of  any  part  of 
a  plant  is  to  re- 
move the  part  in 
question  and  see 
how  the  plant  be- 
haves afterward. 

EXPERIMENT  V1 

Are  the  Cotyledons 
of  a  Pea  of  any  Use 
to  the  Seedling  ?  — 

Sprout  several  peas  on 
blotting  paper.  When 
the  plumules  appear, 
carefully  cut  away  the  cotyledons  from  some  of  the  seeds.  Place  on 
a  perforated  cork,  as  shown  in  Fig.  4,  one  or  two  seedlings  from 

1  May  be  a  home  experiment. 
14 


FIG.  4.  — Germinating  Peas,  growing  in  Water,  one 
deprived  of  its  Cotyledons. 


STORAGE  OF  FOOD  IN  THE  CELLS         15 

which  the  cotyledons  have  been  cut,  and  as  many  which  have  not 
been  mutilated,  and  allow  the  roots  to  extend  into^  the  water.  Let 
them  grow  for  some  days,  or  even  weeks,  and  note  results. 

16.  Food  stored  in  Seeds  in  Relation  to  Growth  after 

Germination If  two  kinds  of  seeds  of  somewhat  similar 

character,  one  kind  large  and  the  other  small,  are  allowed 
to  germinate  and  grow  side  by  side,  some  important  infer- 
ences may  be  drawn  from  their  relative  rate  of  growth. 

EXPERIMENT   VI1 

Does  tne  Amount  of  Material  in  the  Seed  have  anything  to  do  with 
the  Rate  of  Growth  of  the  Seedling  ?  —  Germinate  ten  or  more 
clover  seeds,  and  about  the  same  number  of  peas,  on  moist  blotting 
paper  under  a  bell-jar.  After  they  are  well  sprouted,  transfer  both 
kinds  of  seeds  to  fine  cotton  netting,  stretched  across  wide-mouthed 
jars  nearly  full  of  water.  The  roots  should  dip  into  the  water,  but 
the  seeds  must  not  do  so.  Allow  the  plants  to  grow  until  the  peas 
are  from  four  to  six  inches  high. 

Some  of  the  growth  in  each  case  depends  on  material 
gathered  from  the  air  and  water,  but  most  of  it,  during  the 
very  early  life  of  the  plant,  is  due  to  the  reserve  material 
stored  in  the  seed.  Where  is  it  in 
the  seeds  so  far  studied  ?  Proof  ? 

17.  Storage  of  Food  outside  of 
the  Embryo.  —  In  very  many  cases 
the  cotyledons  contain  little  food, 

but  there   is  a  Supply  of   it  Stored    FIG.  5.  — Seeds  with  Endosperm, 
.,  -i   T        •  i  i    ji  Longitudinal  Sections. 

in  the  seed  beside  or  around  them 

I,  asparagus  (magnified). 
(JblgS.  Z,  O,  ailO.  O).  II,  poppy  (magnified). 

18.  Examination  of  the  Four-o'clock  Seed.  —  Examine  the  exter- 
nal surface  of  a  seed2  of  the  four-o'clock,  and  try  the  hardness  of 

1  May  be  a  home  experiment.         2  Strictly  speaking,  a  fruit. 


16 


FOUNDATIONS    OF   BOTANY 


the  outer  coat  by  cutting  it  with  a  knife.  From  seeds  which  have 
been  soaked  in  water  at  least  twenty-four  hours  peel  off  the  coatings 
and  sketch  the  kernel.  Make  a  cross-section  of  one  of  the  soaked 
seeds  which  has  not  been  stripped  of  its  coatings,  and  sketch  the  sec- 
tion as  seen  with  the  magnifying  glass,  to  show  the  parts,  especially 
the  two  cotyledons,  lying  in  close  contact  and  encircling  the  white, 
starchy-looking  endosperm.1 

The  name  endosperm  is  applied  to  food  stored  in  parts  of  the 
seed  other  than  the  embryo.2  With  a  mounted  needle  pick  out  the 
little  almost  spherical  mass  of  endosperm  from  inside  the  cotyledons 
of  a  seed  which  has  been  deprived  of 
its  coats,  and  sketch  the  embryo,  noting 
how  it  is  curved  so  as  to  enclose  the 
endosperm  almost  completely. 

19.  Examination  of  the  Kernel  of  In- 
dian Corn.  —  Soak  some  grains  of  large 
yellow  field  corn  3  for  about  three  days. 

Sketch  an  unsoaked  kernel,  so  as  to 
show  the  grooved  side,  where  the  germ 
lies.  Observe  how  this  groove  has  be- 
come partially  filled  up  in  the  soaked 

FIG.  6.  —  Lengthwise  Section  of  kernels. 

Grain  of  Corn.    (Magnified  Remove    the   thin,  tough   skin   from 
about  three  times.) 

y,yellow,oilypartof  endosperm;  one  of  flatter,  and  notice  its  transpar- 

w,  white,  starchy  part  of  en-  ency.     This  skin  —  the  bran  of  unsifted 

dosperm ;  p,  plumule  ;  s,  the  com  meal  _  doeg  not  exactly  correspond 

shield  (cotyledon),  in  contact  .    .                           .         ,. 

with  the  endosperm  f or  absorp-  to  the  testa  and  inner  coat  of  ordinary 

tion  of  food  from  it ;  r,  the    seeds,  since  the  kernel  of  corn,  like  all 
primary  root.  Qther   graing    (and  Uke   the  geed  of  the 

four-o'clock),  represents  not  merely  the  seed,  but  also  the  seed-vessel 
in  which  it  was  formed  and  grew,  and  is  therefore  a  fruit. 

1  Buck  wheat  furnishes  another  excellent  study  in  seeds  with  endosperm. 
Like  that  of  the  four-o'clock,  it  is,  strictly  speaking,  a  fruit ;  so  also  is  a  grain 
of  corn. 

2  In  the  squash  seed  the  green  layer  which  covered  the  embryo  represents 
the  remains  of  the  endosperm. 

3  The  varieties  with  long,  flat  kernels,  raised  in  the  Middle  and  Southern 
States  under  the  name  of  "  dent  corn,"  are  the  best. 


STORAGE   OF   FOOD   IN  THE    SEED  17 

Cut  sections  of  the  soaked  kernels,  some  transverse,  some  length- 
wise and  parallel  to  the  flat  surfaces,  some  lengthwise  and  at  right 
angles  to  the  flat  surfaces.  Try  the  effect  of  staining  some  of  these 
sections  with  iodine  solution. 

Make  a  sketch  of  one  section  of  each  of  the  three  kinds,  and  label 
the  dirty  white  portion,  of  cheesy  consistency,  embryo  ;  and  the  yel- 
low portions,  and  those  which  are  white  and  floury,  endosperm. 

Chip  off  the  endosperm,  from  one  kernel  so  as  to  remove  the 
embryo  free  from  other  parts.1  Notice  its  form,  somewhat  triangular 
in  outline,  sometimes  nearly  the  shape  of  a  beechnut,  in  other  speci- 
mens nearly  like  an  almond. 

Estimate  what  proportion  of  the  entire  bulk  of  the  soaked  kernel 
is  embryo. 

Split  the  embryo  lengthwise  so  as  to  show  the  slender,  somewhat 
conical  plumule.2 

20.  Corn  Seedlings  deprived  of  Endosperm — An  experi- 
ment parallel  to  No.  V  serves  to  show  the  function  and 
the  importance  of  the  endosperm  of  Indian  corn. 

EXPERIMENT   VII 

Of  how  much  Use  to  the  Corn  Seedling  is  the  Endosperm  ?  —  Sprout 
kernels  of  corn  on  blotting  paper.  When  they  get  fairly  started, 
cut  away  the  endosperm  carefully  from  several  of  the  seeds.  Sus- 
pend on  mosquito  netting  on  the  surface  of  water  in  the  same  jar 
two  or  three  seedlings  which  have  had  their  endosperm  removed,  and 
as  many  which  have  not  been  mutilated.  Let  them  grow  for  some 
weeks,  ;md  note  results. 

21.  Starch Most     common    seeds     contain    starch. 

Every  one  knows  something  about  the  appearance  of  ordi- 

1  The  embryo  may  be  removed  with  great  ease  from  kernels  of  rather  ma- 
ture green  corn.    Boil  the  corn  for  about  twenty  minutes  on  the  cob,  then  pick 
the  kernels  off  one  by  one  with  the  point  of  a  knife.    They  may  be  preserved 
indefinitely  in  alcohol  of  50  or  75%. 

2  The  teacher  may  well  consult  Figs.  5(5-01,  inclusive,  in  Gray's  Structural 
Botany. 


18  FOUNDATIONS   OF  BOTANY 

nary  commercial  starch  as  used  in  the  laundry,  and  as 
sold  for  food  in  packages  of  cornstarch.  When  pure  it 
is  characterized  not  only  by  its  lustre,  but  also  by  its 
peculiar  velvety  feeling  when  rubbed  between  the  fingers. 

22.  The  Starch  Test It  is  not  always  easy  to  recog- 
nize at  sight  the  presence  of  starch  as  it  occurs  in  seeds, 
but  it  may  be  detected  by  a  very  simple  chemical  test, 
namely,  the  addition  of  a  solution  of  iodine.1 

EXPERIMENT   VIII 2 

Examination  of  Familiar  Seeds  with  Iodine.  —  Cut  in  two  with  a 
sharp  knife  the  seeds  to  be  experimented  on,  then  pour  on  each,  drop 
by  drop,  some  of  the  iodine  solution.  Only  a  little  is  necessary ; 
sometimes  the  first  drop  is  enough. 

If  starch  is  present,  a  blue  color  (sometimes  almost  black)  will 
appear.  If  no  color  is  obtained  in  this  way,  boil  the  pulverized 
seeds  for  a  moment  in  a  few  drops  of  water,  and  try  again. 

Test  in  this  manner  corn,  wheat  (in  the  shape  of  flour),  oats  (in 
oatmeal),  barley,  rice,  buckwheat,  flax,  rye,  sunflower,  four-o'clock, 
morning-glory,  mustard  seed,  beans,  peanuts,  Brazil-nuts,  hazelnuts, 
and  any  other  seeds  that  you  can  get.  Report  your  results  in  tabu- 
lar form  as  follows : 

MUCH  STARCH  LITTLE  STARCH  No  STARCH 

Color :  blackish  or        Color :  pale  blue  or        Color :  brown,  orange, 
dark  blue.  greenish.  or  yellowish. 

23.  Microscopical  Examination  of  Starch.3  —  Examine  starch  in 
water  with  a  rather  high  power  of  the  microscope  (not  less  than  200 
diameters). 

1  The  tincture  of  iodine  sold  at  the  drug-stores  will  do,  but  the  solution 
prepared  as  directed  in  the  Handbook  answers  better.  This  may  be  made  up 
in  quantity,  and  issued  to  the  pupils  in  drachm  vials,  to  be  taken  home  and 
used  there,  if  the  experimenting  must  be  done  outside  of  the  laboratory  or  the 
schoolroom.  2  May  be  a  home  experiment. 

8  At  this  point  the  teacher  should  give  a  brief  illustrated  talk  on  the  con- 
struction and  theory  of  the  compound  microscope. 


STORAGE  OF  FOOD  IN  THE  SEED 


19 


Pulp  scraped  from  a  potato,  that  from  a  canna  rootstock,  wheat 
flour,  the  finely  powdered  starch  sold  under  the  commercial  name  of 
"cornstarch"  for  cooking,  oat- 
meal, and  buckwheat  finely  pow- 
dered in  a  mortar,  will  furnish 
excellent  examples  of  the  shape 
and  markings  of  starch  grains. 
Sketch  all  of  the  kinds  exam- 
ined, taking  pains  to  bring  out 
the  markings.1  Compare  the 
sketches  with  Figs.  7  and  8. 

With  a  medicine-dropper  or  a 
very  small  pipette  run  in  a  drop       FIG.  7.  —  Caima  starch.    (Magnified 
of  iodine  solution  under  one  edge 

of  the  cover-glass,  at  the  same  time  withdrawing  a  little  water  from 
the   margin    opposite  by   touching  to   it  a  bit  of   blotting  paper. 


"&OOOQOPOOOOO 

m C — •H—^s-Z'ttr-^  f~t  i-^&2=Z?s — i 


0° 


FIG.  8.  — Section  through  Exterior  Part  of  a  Grain  of  Wheat. 

c,  cuticle  or  outer  layer  of  bran ;  ep,  epidermis ;  m,  layer  beneath  epidermis ;  gu, 
sch,  layers  of  hull  next  to  seed-coats ;  br,  n,  seed-coats ;  Kl,  layer  containing 
proteld  grains  ;  st,  cells  of  the  endosperm  filled  with  starch.  (Greatly  magnified. ) 

1  The  markings  will  be  seen  more  distinctly  if  care  is  taken  not  to  admit 
top  much  light  to  the  object.  Rotate  the  diaphragm  beneath  the  stage  of  the 
microscope,  or  otherwise  regulate  the  supply  of  light,  until  the  opening  is 
found  which  gives  the  best  effect. 


20  FOUNDATIONS   OF   BOTANY 

Examine  again  and  note  the  blue  coloration  of  the  starch  grains  and 
the  unstained  or  yellow  appearance  of  other  substances  in  the  field. 
Cut  very  thin  slices  from  beans,  peas,  or  kernels  of  corn  ;  mount  in 
water,  stain  as  above  directed,  and  draw  as  seen  under  the  microscope. 
Compare  with  Figs.  7  and  8.1  Note  the  fact  that  the  starch  is  not 
packed  away  in  the  seeds  in  bulk,  but  that  it  is  enclosed  in  little 
chambers  or  cells. 

24.  Plant-Cells.  —  Almost  all  the  parts  of  the  higher 
plants  are  built  up  of  little  separate  portions  called  cells. 
The  cell  is  the  unit  of  plant-structure,  and  bears  some- 
thing the  same  relation  to  the  plant  of  which  it  is  a  part 
that  one  cell  of  a  honeycomb  does  to  the  whole  comb. 
But  this  comparison  is  not  a  perfect  one,  for  neither  the 
waxen  wall  of  the  honeycomb-cell  nor  the  honey  within  it 
is  alive,  while  every  plant-cell  is  or  has  bean  alive.  And 
even  the  largest  ordinary  honeycomb  consists  of  only  a 
few  hundred  cells,  while  a  large  tree  is  made  up  of  very 
many  miillons  of  cells.  The  student  must  not  conceive 
of  the  cell  as  merely  a  little  chamber  or  enclosure.  The 
living,  more  or  less  liquid,  or  mucilage-like,  or  jelly-like 
substance  known  as  protoplasm,  which  forms  a  large  portion 
of  the  bulk  of  living  and  growing  cells,  is  the  all-important 
part  of  such  a  cell.  Professor  Huxley  has  well  called 
this  substance  "  the  physical  basis  of  life."  Cells  are  of 
all  shapes  and  sizes,  from  little  spheres  a  ten-thousand th 
of  an  inch  or  less  in  diameter  to  slender  tubes,  such  as 
fibers  of  cotton,  several  inches  long.  To  get  an  idea  of 
the  appearance  of  some  rather  large  cells,  scrape  a  little 
pulp  from  a  ripe,  mealy  apple,  and  examine  it  first  with 

1  The  differentiation  between  the  starch  grains,  the  other  cell-contents, 
and  the  cell-walls  will  appear  better  in  the  drawings  if  the  starch  grains  are 
sketched  with  blue  ink. 


STORAGE   OF   FOOD   IN   THE   SEED  21 

a  strong  magnifying  glass,  then  with  a  moderate  power  of 
the  compound  microscope.  To  see  how  dead,  dry  cell- 
walls,  with  nothing  inside  them,  look,  examine  (as  before) 
a  very  thin  slice  of  elder  pith,  sunflower  pith,  or  pith  from 
a  dead  cornstalk.  Look  also  at  the  figures  in  Chapter  VI 
of  this  book.  Notice  that  the  simplest  plants  (Chapter  XX) 
consist  of  a  single  cell  each.  The  study  of  the  structure 
of  plants  is  the  study  of  the  forms  which  cells  and  groups 
of  cells  assume,  and  the  study  of  plant  physiology  is  the 
study  of  what  cells  and  cell  combinations  do. 

25,  Absorption  of  Starch  from  the  Cotyledons.  —  Examine  with 
the  microscope,  using  a  medium  power,  soaked  beans  and  the  cotyle- 
dons from  seedlings  that  have  been  growing  for  three  or  four  weeks. 
Stain  the  sections  with  iodine  solution,  and  notice  how  completely 
the  clusters  of  starch  grains  that  -filled  most  of  the  cells  of  the  un- 
sprouted  cotyledons  have  disappeared  from  the  shriveled  cotyledons 
of  the  seedlings.     A  few  grains  may  be  left,  but  they  have  lost  their 
sharpness  of  outline. 

26,  Oil.  --  The    presence    of    oil    in    any    considerable 
quantity  in  seeds  is  not  as  general  as  is  the  presence  of 
starch,  though  in  many  common  seeds   there   is  a  good 
deal  of  it. 

Sometimes  the  oil  is  sufficiently  abundant  to  make  it 
worth  while  to  extract  it  by  pressure,  as  is  done  with  flax- 
seed,  cotton-seed,  the  seeds  of  some  plants  of  the  cress 
family,  the  "  castor  bean,"  and  other  seeds. 

27,  Dissolving  Oil  from  Ground  Seeds.  —  It  is  not  possi- 
ble easily  to  show  a  class  how  oil  is  extracted  from  seeds 
by  pressure ;  but  there  are  several  liquids  which  readily 
dissolve  oils  and  yet  have  no  effect  on  starch  and  most  of 
the  other  constituents  of  seeds. 


22  FOUNDATIONS   OF  BOTANY 


EXPERIMENT   IX 

Extraction  of  Oil  by  Ether  or  Benzine.  —  To  a  few  ounces  of 
ground  flaxseed  add  an  equal  volume  of  ether  or  benzine.  Let  it 
stand  ten  or  fifteen  minutes  and  then  filter.  Let  the  liquid  stand  in 
a  saucer  or  evaporating  dish  in  a  good  draught  till  it  has  lost  the 
odor  of  the  ether  or  benzine. 

Describe  the  oil  which  you  have  obtained. 

Of  what  use  would  it  have  been  to  the  plant  ? 

If  the  student  wishes  to  do  this  experiment  at  home  for  himself, 
he  should  bear  in  mind  the  following : 

Caution.  —  Never  handle  benzine  or  ether  near  a  flame  or  stove. 

A  much  simpler  experiment  to  find  oil  in  seeds  may  readily  be 
performed  by  the  pupil  at  home.  Put  the  material  to  be  studied,  e.g., 
flaxseed  meal,  corn  meal,  wheat  flour,  cotton-seed  meal,  buckwheat 
flour,  oatmeal,  and  so  on,  upon  little  labeled  pieces  of  white  paper, 
one  kind  of  flour  or  meal  on  each  bit  of  paper.  Place  all  the  papers, 
with  their  contents,  on  a  perfectly  clean  plate,  free  from  cracks,  or 
on  a  clean  sheet  of  iron,  and  put  this  in  an  oven  hot  enough  nearly 
(but  not  quite)  to  scorch  the  paper.  After  half  an  hour  remove  the 
plate  from  the  oven,  shake  off  the  flour  or  meal  from  each  paper,  and 
note  the  results,  a  more  or  less  distinct  grease  spot  showing  the 
presence  of  oil,  or  the  absence  of  any  stain  that  there  was  little  or 
no  oil  in  the  seed  examined. 

28.  Albuminous  Substances.  —  Albuminous  substances 
or  proteids  occur  in  all  seeds,  though  often  only  in  small 
quantities.  They  have  nearly  the  same  chemical  compo- 
sition as  white  of  egg  and  the  curd  of  milk  among  animal 
substances,  and  are  essential  to  the  plant,  since  the  living 
and  growing  parts  of  all  plants  contain  large  quantities  of 
proteid  material. 

Sometimes  the  albuminous  constituents  of  the  seed  occur 
in  more  or  less  regular  grains  (Fig.  8,  at  Kl) . 

But  much  of  the  proteid  material  of  seeds  is  not  in  any 


STORAGE   OF   FOOD   IN  THE    SEED  23 

form  in  which  it  can  be  recognized  under  the  microscope. 
One  test  for  its  presence  is  the  peculiar  smell  which  it 
produces  in  burning.  Hair,  wool,  feathers,  leather,  and 
lean  meat  all  produce  a  well-known  sickening  smell  when 
scorched  or  burned,  and  the  similarity  of  the  proteid  mate- 
rial in  such  seeds  as  the  bean  and  pea  to  these  substances 
is  shown  by  the  fact  that  scorching  beans  and  similar 
seeds  give  off  the  familiar  smell  of  burnt  feathers. 

29.  Chemical  Tests  for   Proteids.  —  All  proteids   (and 
very  few  other  substances)  are  turned  yellow  by  nitric 
acid,  and  this  yellow  color  becomes  deeper  or  even  orange 
when  the  yellowish  substance  is  moistened  with  ammonia. 
They  are  also  turned  yellow  by  iodine  solution.     Most 
proteids  are  turned  more  or  less  red  by  the  solution  of 
nitrate  of  mercury  known  as  Millon's  reagent.1 

EXPERIMENT  X 

Detection  of  Proteids  in  Seeds.  —  Extract  the  germs  from  some 
soaked  kernels  of  corn  and  bruise  them;  soak  some  wheat-germ  meal 
for  a  few  hours  in  warm  water,  or  wash  the  starch  out  of  wheat- 
flour  dough ;  reserving  the  latter  for  use,  place  it  in  a  white  saucer  or 
porcelain  evaporating  dish,  and  moisten  well  with  Millon's  reagent 
or  with  nitric  acid ;  examine  after  fifteen  minutes. 

30.  The  Brazil-Nut  as  a  Typical  Oily  Seed.  —  Not  many 
familiar  seeds  are  as  oily  as  the  Brazil-nut.     Its  large  size 
makes  it  convenient  for  examination,  and  the  fact  that  this 
nut  is  good  for  human  food  makes  it  the  more  interesting 
to  investigate  the  kinds  of  plant-food  which  it  contains. 

i  See  Handbook. 


24  FOUNDATIONS    OF    BOTANY 


EXPERIMENT  XI 

Testing  Brazil-Nuts  for  Plant-Foods.  —  Crack  fifteen  or  twenty 
Brazil-nuts,  peel  oif  the  brown  coating  from  the  kernel  of  each,  and 
then  grind  the  kernels  to  a  pulp  in  a  mortar.  Shake  up  this  pulp 
with  ether,  pour  upon  a  paper  filter,  and  wash  with  ether  until  the 
washings  when  evaporated  are  nearly  free  from  oil.  The  funnel 
containing  the  filter  should  be  kept  covered  as  much  as  possible 
until  the  washing  is  finished.  Evaporate  the  filtrate  to  procure  the 
oil,  which  may  afterwards  be  kept  in  a  glass-stoppered  bottle.  Dry 
the  powder  which  remains  on  the  filter  and  keep  it  in  a  wide- 
mouthed  bottle.  Test  portions  of  this  powder  for  proteids  and  for 
starch.  Explain  the  results  obtained. 

31.  Other  Constituents  of  Seeds.  —  Besides  the  substances 
above  suggested,  others  occur  in  different  seeds.  Some 
of.  these  are  of  use  in  feeding  the  seedling,  others  are  of 
value  in  protecting  the  seed  itself  from  being  eaten  by 
animals  or  in  rendering  it  less  liable  to  decay.  In  such 
seeds  as  that  of  the  nutmeg,  the  essential  oil  which  gives 
it  its  characteristic  flavor  probably  makes  it  unpalatable 
to  animals  and  at  the  same  time  preserves  it  from  decay. 

Date  seeds  are  so  hard  and  tough  that  they  cannot  be 
eaten  and  do  not  readily  decay.  Lemon,  orange,  horse- 
chestnut  and  buckeye  seeds  are  too  bitter  to  be  eaten,  and 
the  seeds  of  the  apple,  cherry,  peach,  and  plum  are  some- 
what bitter. 

The  seeds  of  larkspur,  thorn-apple,1  croton,  the  castor- 
oil  plant,  nux  vomica,  and  many  other  kinds  of  plants 
contain  active  poisons. 

1  Datura,  commonly  called  "  Jimpson  weed." 


CHAPTER    III 


MOVEMENTS,    DEVELOPMENT,   AND  MORPHOLOGY   OF 
THE   SEEDLING 

32.  How  the  Seedling  breaks  Ground.  —  As  the  student 
has  already  learned  by  his  own  observations,  the  seedling 
does  not  always  push  its  way  straight  out  of  the  ground. 
Corn,  like  all  the  other  grains  and  grasses,  it  is  true,  sends 
a  tightly  rolled,  pointed  leaf  vertically  upward  into  the 
air.  But  the  other  seedlings  examined  usually  will  not 
be  found  to  do  anything  of  the  sort.  The  squash  seedling 
is  a  good  one  in  which  to  study  what  may 
be  called  the  arched  hypocotyl 
type  of  germination.  If  the  co 
seed  when  planted  is  laid  hori- 

M 


A  BCD  K 

FIG.  9.  — Successive  Stages  in  the  Life  History  of  the  Squash  Seedling. 

GG,  the  surface  of  the  ground  ;  r,  primary  root ;  r',  secondary  root ;  c,  hypocotyl ; 
a,  arch  of  hypocotyl ;  co,  cotyledons . 

zontally  on  one  of  its  broad  surfaces,  it  usually  goes  through 
some  such  changes  of  position  as  are  shown  in  Fig.  y. 

25 


26  FOUNDATIONS   OF   BOTANY 

The  seed  is  gradually  tilted  until,  at  the  time  of  their 
emergence  from  the  ground  (at  (7),  the  cotyledons  are 
almost  vertical.  The  only  part  above  the  ground-line  6r,  6r, 
at  this  period,  is  the  arched  hypocotyl.  Once  out  of  ground, 
the  cotyledons  soon  rise,  until  (at  E)  they  are  again  ver- 
tical, but  with  the  other  end  up  from  that  which  stood 
highest  in  0.  Then  the  two  cotyledons  separate  until 
they  once  more  lie  horizontal,  pointing  away  from  each 
other. 

Can  you  suggest  any  advantage  which  the  plant  derives 
from  having  the  cotyledons  dragged  out  of  the  ground 
rather  than  having  them  pushed  out,  tips  first  ? 

33,  Cause  of  the  Arch.  —  It  is  evident  that  a  flexible 
object  like  the  hypocotyl,  when  pushed  upward  through  the 
earth,  might  easily  be  bent  into  an  arch  or  loop.    Whether 
the  shape  which  the  hypocotyl  assumes  is  wholly  caused 
by  the  resistance  of  the  soil  can  best  be  ascertained  by 
an  experiment. 

EXPERIMENT   XII 

Is  the  Arch  of  the  Hypocotyl  due  to  the  Pressure  of  the  Soil  on  the 
Rising  Cotyledons  ?  —  Sprout  some  squash  seeds  on  wet  paper  under 
a  bell-glass,  and  when  the  root  is  an  inch  or  more  long,  hang  several 
of  the  seedlings,  roots  down,  in  little  stirrups  made  of  soft  twine, 
attached  by  beeswax  and  rosin  mixture  to  the  inside  of  the  upper 
part  of  a  bell-glass.  Put  the  bell-glass  on  a  large  plate  or  a  sheet  of 
glass  on  which  lies  wet  paper  to  keep  the  air  moist.  Note  whether 
the  seedlings  form  hypocotyl  arches  at  all  and,  if  so,  whether  the 
arch  is  more  or  less  perfect  than  that  formed  by  seedlings  growing 
in  earth,  sand,  or  sawdust. 

34.  What  pushes  the  Cotyledons   up?  —  A  very  little 
study  of  any  set  of  squash  seedlings,  or  even  of  Fig.  9,  is 


MORPHOLOGY   OF  THE   SEEDLING  27 

sufficient  to  show  that  the  portion  of  the  plant  where 
roots  and  hypocotyl  are  joined  neither  rises  nor  sinks,  but 
that  the  plant  grows  both  ways  from  this  part  (a  little 
above  rr  in  Fig.  9,  A  and  J5).  It  is  evident  that  as  soon  as 
the  hypocotyl  begins  to  lengthen  much  it  must  do  one  of 
two  things  :  either  push  the  cotyledons  out  into  the  air  or 
else  force  the  root  down  into  the  ground  as  one  might 
push  a  stake  down.  What  changes  does  the  plantlet 
undergo,  in  passing  from  the  stage  shown  at  A  to  that 
of  B  and  of  C\  making  it  harder  and  harder  for  the  root 
to  be  thrust  downward? 

35.  Use  of  the  Peg.  —  Squash  seedlings  usually  (though 
not  always)  form  a  sort  of  knob  on  the  hypocotyl.     This  is 
known  as  the  peg.     Study  a  good  many  seedlings  and  try 
to  find  out  what  the  lengthening  of  the  hypocotyl,  between 
the  peg  and  the  bases  of  the  cotyledons,  does  for  the  little 
plant.     Set  a  lot  of  squash  seeds,  hilum  down,  in  moist 
sand  or  sawdust  and  see  whether  the  peg  is  more  or  less 
developed  than  in  seeds  sprouted  lying  on  their  sides,  and 
whether  the  cotyledons  in  the  case  of  the  vertically  planted 
seeds  usually  come  out  of  the  ground  in  the  same  condi- 
tion as  do  those  shown  in  Fig.  9. 

36.  Discrimination  between  Root  and  Hypocotyl.  —  It  is 
not  always  easy  to  decide  by  their  appearance   and  be- 
havior what  part  of  the  seedling  is  root  and  what  part  is 
hypocotyl.     In  a  seedling  visibly  beginning  to  germinate, 
the  sprout,  as  it  is  commonly  called,  which  projects  from 
the  seed  might  be  either  root  or  hypocotyl  or  might  consist 
of  both  together,  so  far  as  its  appearance  is  concerned.    A 
microscopic  study  of  the  cross-section  of  a  root,  compared 
with  one  of  the  hypocotyl,  would  show  decided  differences 


28  FOUNDATIONS   OF  BOTANY 

of  structure  between  the  two.  Their  mode  of  growth  is 
also  different,  as  the  pupil  may  infer  after  he  has  tried 
Exp.  XIV. 

37.  Discrimination  by  Staining.  —  For  some  reason,  per- 
haps because  the  skin  or  epidermis  of  the  young  root  is 
not  so  water-proof  as  that  of  the  stem,  the  former  stains 
more  easily  than  the  latter  does. 

EXPERIMENT   XIII 

The  Permanganate  Test.  —  Make  a  solution  of  potassium  perman- 
ganate in  water,  by  adding  about  four  parts,  by  weight,  of  the  crystal- 
lized permanganate  to  100  parts  of  water.  Drop  into  the  solution 
seedlings,  e.g.,  of  all  the  kinds  that  have  been  so  far  studied,  each  in 
its  earliest  stage  of  germination  (that  is,  when  the  root  or  hypocotyl 
has  pushed  out  of  the  seed  half  an  inch  or  less),  and  also  at  one  or 
two  subsequent  stages.  After  the  seedlings  have  been  in  the  solu- 
tion from  three  to  five  minutes,  or  as  soon  as  the  roots  are  consider- 
ably stained,  pour  off  (and  save)  the  solution  and  rinse  the  plants 
with  plenty  of  clear  water.  Sketch  one  specimen  of  each  kind,  col- 
oring the  brown-stained  part,  which  is  root,  in  some  way  so  as  to 
distinguish  it  from  the  unstained  hypocotyl.  Note  particularly  how 
much  difference  there  is  in  the  amount  of  lengthening  in  the  several 
kinds  of  hypocotyl  examined.  Decide  whether  the  peg  of  the  squash 
seedling  is  an  outgrowth  of  hypocotyl  or  of  root. 

38.  Disposition  made  of  the  Cotyledons.  —  As  soon  as 
the  young  plants  of  squash,  bean,  and  pea  have  reached 
a  height  of  three  or  four  inches  above  the  ground  it  is 
easy  to  recognize  important    differences  in  the  way  in 
which  they  set  out  in  life. 

The  cotyledons  of  the  squash  increase  greatly  in  sur- 
face, acquire  a  green  color  and  a  generally  leaf-like  appear- 
ance, and,  in  fact,  do  the  work  of  ordinary  leaves.  In 


MORPHOLOGY   OF   THE   SEEDLING  29 

such  a  case  as  this  the  appropriateness  of  the  name  seed- 
leaf  is  evident  enough,  —  one  recognizes  at  sight  the  fact 
that  the  cotyledons  are  actually  the  plant's  first  leaves. 
In  the  bean  the  leaf-like  nature  of  the  cotyledons  is  not 
so  clear.  They  rise  out  of  the  ground  like  the  squash 
cotyledons,  but  then  gradually  shrivel  away,  though  they 
may  first  turn  green  and  somewhat  leaf-like  for  a  time. 

In  the  pea  (as  in  the  acorn,  the  horse-chestnut,  and 
many  other  seeds)  we  have  quite  another  plan,  the  under- 
ground type  of  germination.  Here  the  thick  cotyledons 
no  longer  rise  above  ground  at  all,  because  they  are  so 
gorged  with  food  that  they  could  never  become  leaves ; 
but  the  young  stem  pushes  rapidly  up  from  the  surface 
of  the  soil. 

The  development  of  the  plumule  seems  to  depend  some- 
what on  that  of  the  cotyledons.  The  squash  seed  has 
cotyledons  which  are  not  too  thick  to  become  useful  leaves, 
and  so  the  plant  is  in  no  special  haste  to  get  ready  any 
other  leaves.  The  plumule,  therefore,  cannot  be  found 
with  the  magnifying  glass  in  the  unsprouted  seed,  and  is 
almost  microscopic  in  size  at  the  time  when  the  hypocotyl 
begins  to  show  outside  of  the  seed-coats. 

In  the  bean  and  pea,  on  the  other  hand,  since  the  cotyle- 
dons cannot  serve  as  foliage  leaves,  the  later  leaves  must 
be  pushed  forward  rapidly.  In  the  bean  the  first  pair  are 
already  well  formed  in  the  seed.  In  the  pea  they  cannot 
be  clearly  made  out,  since  the  young  plant  forms  several 
scales  on  its  stem  before  it  produces  any  full-sized  leaves, 
and  the  embryo  contains  only  hypocotyl,  cotyledons,  and  a 
sort  of  knobbed  plumule,  well  developed  in  point  of  size, 
representing  the  lower  scaly  part  of  the  stem. 


30  FOUNDATIONS   OF   BOTANY 

39.  Root,  Stem,  and  Leaf.  —  By  the  time  the  seedling  is 
well  out  of  the  ground  it,  in  most  cases,  possesses  the  three 
kinds  of  vegetative  organs,  or  parts  essential  to  growth,  of 
ordinary  flowering  plants,  i.e.,  the  root,  stem,  and  leaf,  ^ar, 
as  they  are  sometimes  classified,  root  and  shoot.     All  of 
these  organs   may   multiply  and  increase  in  size  as  the 
plant  grows   older,   and  their  mature    structure   will  be 
studied  in  later  chapters,  but  some  facts  concerning  them 
can  best  be  learned  by  watching  their  growth  from  the 
outset. 

40.  Young  Roots  grown  for  Examination.  —  Roots  grow- 
ing in  sand  or  ordinary  soil  cling  to  its  particles  so  tena- 
ciously that  they  cannot  easily  be  studied,  and  those  grown 
in  water  have  not  quite  the  same  form  as  soil-roots.    Roots 
grown  in  damp  air  are  best  adapted  for  careful  study. 

41.  Elongation  of  the  Root.  —  We  know  that  the  roots 
of  seedlings  grow  pretty  rapidly  from  the  fact  that  each 
day  finds  them   reaching  visibly  farther  down  into  the 
water  or  other  medium  in  which  they  are  planted.     A 
sprouted  Windsor  bean  in  a  vertical  thistle-tube  will  send 
its  root  downward  fast  enough  so  that  ten  minutes'  watch- 
ing through  the  microscope  will  suffice  to  show  growth. 
To  find  out  just  where  the  growth  goes  on  requires  a 
special  experiment. 

EXPERIMENT   XIV 

In  what  Portions  of  the  Root  does  its  Increase  in  Length  take  Place  ? 
—  Sprout  some  peas  on  moist  blotting  paper  in  a  loosely  covered  tum- 
bler. When  the  roots  are  one  and  a  half  inches  or  more  long,  mark 
them  along  the  whole  length  with  little  dots  made  with  a  bristle 
dipped  in  water-proof  India  ink,  or  a  fine  inked  thread  stretched  on 
a  little  bow  of  whalebone  or  brass  wire. 


MORPHOLOGY   OF   THE   SEEDLING  31 

Transfer  the  plants  to  moist  blotting  paper  under  a  bell-glass  or 
an  inverted  battery  jar  and  examine  the  roots  at  the  end  of  twenty- 
four  hours  to  see  along  what  portions  their  length  has  increased ; 
continue  observations  on  them  for  several  days. 

42.  Root-Hairs.  —  Barley,   oats,   wheat,  red  clover,  or 
buckwheat   seeds    soaked    and    then   sprouted    on    moist 
blotting  paper  afford  convenient    material    for   studying 
root-hairs.     The  seeds  may  be  kept  covered  with  a  watch- 
glass  or  a  clock-glass  while  sprouting.     After  they  have 
begun   to    germinate    well,   care    must  be    taken   not   to 
have  them  kept  in  too  moist  an  atmosphere,  or  very  few 
root-hairs   will   be    formed.      Examine    with   the    magni- 
fying  glass    those    parts    of   the  root  which    have    these 
appendages. 

Try  to  find  out  whether  all  the  portions  of  the  root  are 
equally  covered  with  hairs  and,  if  not,  where  they  are 
most  abundant.  (See  also  Sect.  53.) 

The  root-hairs  in  plants  growing  under  ordinary  condi- 
tions are  surrounded  by  the  moist  soil  and  wrap  them- 
selves around  microscopical  particles  of  earth  (Fig.  11). 
Thus  they  are  able  rapidly  to  absorb  through  their  thin 
walls  the  soil-water,  with  whatever  mineral  substances  it 
has  dissolved  in  it. 

43.  The  Young   Stem.  —  The  hypocotyl,  or  portion  of 
the  stem  which  lies  below  the  cotyledons,  is  the  earliest 
formed  portion  of  the  stem.     Sometimes  this  lengthens  but 
little ;  often,  however,  as  the  student  knows  from  his  own 
observations,  the  hypocotyl  lengthens  enough  to  raise  the 
cotyledons  well  above  ground,  as  in  Fig.  10. 

The  later  portions  of  the  stem  are  considered  to  be 
divided  into  successive  nodes,  —  places  at  which  a  leaf  (or 


32 


FOUNDATIONS   OF   BOTANY 


a  scale  which  represents  a  leaf)  appears;  and  inter-nodes, — 
portions  between  the  leaves. 

The  student  should  watch  the  growth  of  a  seedling 
bean  or  pea  and  ascertain  by  actual  measurements  whether 
the  internodes  lengthen  after  they  have  once  been  formed, 
and  if  so,  for  how  long  a  time  the  increase  continues. 


b 


FIG.  10. 


FIG.  10.  —  A  Turnip  Seedling,  with  the*t!otyledons  developed  into  Temporary  Leaves. 
h,  root-hairs  from  the  primary  root ;   b,  bare  portion  of  the  root,  on  which  no 
hairs  have  as  yet  been  produced. 

FIG.  11.  — Cross-Section  of  a  Root,  a  good  deal  magnified,  showing  root-hairs  attached 
to  particles  of  soil,  and  sometimes  enwrapping  these  particles. 

44.  The  First  Leaves.  —  The  cotyledons  are,  as  already 
explained,  the  first  leaves  which  the  seedling  possesses,  — 
even  if  a  plumule  is  found  well  developed  in  the  seed,  it 
was  formed  after  the  cotyledons.  In  those  plants  which 
have  so  much  food  stored  in  the  cotyledons  as  to  render 
these  unfit  ever  to  become  useful  foliage  leaves,  there  is 
little  or  nothing  in  the  color,  shape,  or  general  appearance 


MORPHOLOGY   OF   THE   SEEDLING  33 

of  the  cotyledon  to  make  one  think  it  really  a  leaf,  and  it 
is  only  by  studying  many  cases  that  the  botanist  is  enabled 
to  class  all  cotyledons  as  leaves  in  their  nature,  even  if  they 
are  quite  unable  to  do  the  ordinary  work  of  leaves.  The 
study  of  the  various  forms  which  the  parts  or  organs  of  a 
plant  may  assume  is  called  morphology ;  it  traces  the  rela- 
tionship of  parts  which  are  really  akin  to  each  other, 
though  dissimilar  in  appearance  and  often  in  function. 
In  seeds  which  have  endosperm-)  or  food  stored  outside  of 
the  embryo,  the  cotyledons  usually  become  green  and 
leaf-like,  as  they  do,  for  example,  in  the  four-o'clock,  the 
morning-glory,  and  the  buckwheat ;  but  in  the  seeds  of 
the  grains  (which  contain  endosperm)  a  large  portion  of 
the  single  cotyledon  remains  throughout  as  a  thickish 
mass  buried  in  the  seed.  In  a  few  cases,  as  in  the  pea, 
there  are  scales  instead  of  true  leaves  formed  on  the  first 
nodes  above  the  cotyledons,  and  it  is  only  at  about  the 
third  node  above  that  leaves  of  the  ordinary  co 

kind  appear.  In  the  bean  and  some  other 
plants  which  in  general  bear  one  leaf  at  a 
node  along  the  stem,  there  is  a  pair  produced 
at  the  first  node  above  the  cotyledons,  and 
the  leaves  of  this  pair  differ  in  shape  from 
those  which  arise  from  the  succeeding  por- 
tions of  the  stem. 

45.    Classification  of  Plants  by  the  Number  i 

of  their  Cotyledons.  — In  the  pine  family  the     FlG  10  _Ger 
germinating  seed  often  displays  more   than     minating  pine, 
two  cotyledons,  as  shown  in  Fig.  12;  in  the     co'  cotyledons- 
majority   of    common    flowering    plants    the    seed    con- 
tains two  cotyledons,  while  in  the  lilies,  the  rushes,  the 


34 


FOUNDATIONS   OF   BOTANY 


sedges,  the  grasses,  and  some  other  plants,  there  is  but  one 
cotyledon.  Upon  these  facts  is  based  the  division  of  most 
flowering  plants  into  two  great  groups :  the  dicotyledonous 
plants,  which  have  two  seed-leaves,  and  the  monocotyledon- 
ous  plants,  which  have  one  seed-leaf.  Other  important 
differences  nearly  always  accompany  the  difference  in 
number  of  cotyledons,  as  will  be  seen  later. 

46.  Tabular  Review  of  Experiments.  --  Make  out  a 
table  containing  a  very  brief  summary  of  the  experiments 
thus  far  performed,  as  follows : 


NUMBER 

OF 

EXPERIMENT 

OBJECT 

SOUGHT 

MATERIALS 

AND 

APPARATUS 

OPERA- 
TIONS 
PERFORMED 

RESULTS 

INFERENCES 

• 

47.  Review  Sketches.  —  Make  out  a  comparison  of  the 
early  life  histories  of  all  the  other  seedlings  studied,  by 
arranging  in  parallel  columns  a  series  of  drawings  of  each, 


MOKPHOLOGY   OF   THE   SEEDLING 


35 


like  those  of  Fig.  9,  but  in  vertical  series,  the  youngest 
of  each  at  the  top,  thus  : 


BEAN 

PEA 

CORN 

FIRST  STAGE 

SECOND  STAGE 

• 

THIRD  STAGE 

FOURTH  STAGE 

FIFTH  STAGE 

ETC. 

CHAPTER   IV 
ROOTS  l 

48.  Origin  of  Roots The  primary  root  originates  from 

the  lower  end  of  the  hypocotyl,  as  the  student  learned 
from   his    own    observations    on    sprouting    seeds.     The 
branches  of  the  primary  root  are  called  secondary  roots, 
and  the  branches  of   these    are  known   as  tertiary  roots. 
Those  roots  which  occur  on  the  stem  or  in  other  unusual 
places  are  known  as  adventitious  roots.     The  roots  which 
form   so  readily  on    cuttings    of    willow,   southernwood, 
tropseolum,    French    marigold,    geranium    (pelargonium), 
tradescantia,  and  many  other  plants,  when  placed  in  damp 
earth  or  water,  are  adventitious. 

49.  Aerial  Roots.  —While    the  roots  of  most  familiar 
plants  grow  in  the  earth  and  are  known  as  soil-roots,  there 
are  others  which  are  formed  in  the  air,  called  aerial  roots. 
They  serve  various  purposes :  in  some  tropical  air-plants 
(Fig.  13)  they  serve  to  fasten  the  plant  to  the  tree  on 
which  it  establishes  itself,  as  well  as  to  take  in  water  which 
drips  from  branches  and  trunks  above  them,  so  that  these 
plants  require  no  soil  and  grow  in  mid-air  suspended  from 
trees,  which  serve  them  merely  as  supports  ; 2   many  such 

1  To  the  plant  the  root  is  more  important  than  the  stem.  The  author  has, 
however,  treated  the  structure  of  the  latter  more  fully  than  that  of  the  root, 
mainly  because  the  tissues  are  more  varied  in  the  stem  and  a  moderate  knowl- 
edge of  the  more  complex  anatomy  of  the  stem  will  serve  every  purpose. 

a  If  it  can  be  conveniently  managed,  the  class  will  find  it  highly  interesting 
and  profitable  to  visit  any  greenhouse  of  considerable  size,  in  which  the  aerial 
roots  of  orchids  and  aroids  may  be  examined. 


ROOTS 


37 


air-plants  are  grown  in  greenhouses.  In  such  plants  as  the 
ivy  (Fig.  15)  the  aerial  roots  (which  are  also  adventitious) 
hold  the  plant  to  the  wall  or  other  surface  up  which  it  climbs. 

In  the  Indian  corn  (Fig.  14)  roots  are  sent  out  from 
nodes  at  some  dis- 
tance above  the 
ground  and  finally 
descend  until  they 
enter  the  ground. 
They  serve  both  to 
anchor  the  cornstalk 
so  as  to  enable  it  to 
resist  the  wind  and 
to  supply  additional 
water  to  the  plant.1 
They  often  produce 
no  rootlets  until  they 
reach  the  ground. 

50.    Water-Roots.  --Many 
plants,   such    as   the   willow, 
readily  adapt  their  roots  to 
live  either  in  earth  or  in  water, 
and  some,  like  the  little  float-     FIG.  13.— Aerial 
ing  duckweed,  regularly  pro-    Roots  of  an  0reMd' 
duce  roots  which  are  adapted  to  live  in  water 
only.     These  water-roots  often  show  large  and          I 
distinct  sheaths  on  the  ends  of  the  roots,  as,  for  instance, 
in  the  so-called  water-hyacinth.     This  plant  is  especially 
interesting   for  laboratory  cultivation  from  the  fact  that 


1  Specimens  of  tLe  lower  part  of  the  cornstalk,  with  ordinary  roots  and 
aerial  roots,  should  be  dried  and  kept  for  class  study. 


38 


FOUNDATIONS   OF   BOTANY 


-a 


FIG.  14. —  Lower  Part  of  Stem  and  Roots  of  Indian  Corn,  showing  Aerial 
Roots  ( "  Brace-Roots  " ). 

a,  c,  internodes  of  the  stem  ;  6,  d,  e,f,  nodes  of  various  age  bearing  roots.    Most  of 
these  started  as  aerial  roots,  but  all  except  those  from  b  have  now  reached  the  earth. 


ROOTS 


39 


it  may  readily  be  transferred  to  moderately  damp  soil, 
and  that  the  whole  plant  presents  curious  modifications 
when  made  to  grow  in  earth  instead  of  water. 

51.  Parasitic  Roots.1  —  The  dodder,  the  mistletoe,  and  a 
good  many  other  parasites,  live  upon  nourishment  which 
they  steal  from  other  plants,  called  hosts.  The  parasitic 


FIG.  15.  —  Aerial  Adventitious  Eoots  of  the  Ivy. 

roots,  or  haustoria,  form  the  most  intimate  connections 
with  the  interior  portions  of  the  stem  or  the  root,  as  the 
case  may  be,  of  the  host-plant  on  which  the  parasite 
fastens  itself. 

In  the  dodder,  as  is  shown  in  Fig.  16,  it  is  most  inter- 
esting to  notice  how  admirably  the  seedling  parasite  is 
adapted  to  the  conditions  under  which  it  is  to  live.  Rooted 

1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  pp.  171-213. 


40 


FOUNDATIONS   OF   BOTANY 


at  first  in  the  ground,  it  develops  a  slender,  leafless  stem, 
which,  leaning  this  way  and  that,  no  sooner  comes  into 


ABC 

FIG.  16.  —  Dodder,  growing  upon  a  Golden-Rod  Stem. 

s,  seedling  dodder  plants,  growing  in  earth ;  h,  stem  of  host ;  r,  haustoria  or 
parasitic  roots  of  dodder  ;  I,  scale-like  leaves.  A,  magnified  section  of  a  por- 
tion of  willow  stem,  showing  penetration  of  haustoria. 

permanent  contact  with  a  congenial  host  than  it  produces 
haustoria  at  many  points,  gives  up  further  growth  in  its 


ttOOTS 


41 


soil-roots,  and  grows  rapidly  on  the  strength  of  the  sup- 
plies of  ready-made  sap  which  it  obtains  from  the  host. 

52.  Forms  of  Roots The  primary  root  is  that  which 

proceeds  like  a  downward  prolongation  directly  from  the 
lower  end  of  the  hypocotyl.  In  many  cases  the  mature  root- 
system  of  the  plant  contains  one  main  root  much  larger 
than  any  of  its  branches.  This  is  called  a  taproot  (Fig.  17). 

Such  a  root,  if  much  thickened,  would  assume  the  form 


; 


FIG.  17.  —  A  Taproot.         FIG.  18.  —  Fibrous  Roots.          FlG.  19.  — Fascicled  Roots. 

shown  in  the  carrot,  parsnip,  beet,  turnip,  salsify,  or  radish, 
and  is  called  a  fleshy  root.  Some  plants  produce  multiple 
primary  roots,  that  is,  a  cluster  proceeding  from  the  lower 
end  of  the  hypocotyl  at  the  outset.  If  such  roots  become 
thickened,  like  those  of  the  sweet  potato  and  the  dahlia 
(Fig.  19),  they  are  known  as  fascicled  roots. 

Roots  of  grasses,  etc.,  are  thread-like,  and  known  as 
fibrous  roots  (Fig.  18). 

53.  General  Structure  of  Roots The  structure  of  the 

very  young  root  can  be  partially  made  out  by  examining 


42 


FOUNDATIONS   OF   BOTANY 


the  entire  root  with  a  moderate  magnifying  power,  since 
the  whole  is  sufficiently  translucent  to  allow  the  interior 
as  well  as  the  exterior  portion  to  be  studied  while  the  root 
is  still  alive  and  growing. 

Place  some  vigorous  cuttings  of  tradescantia  or  Zebrina,  which 
can  usually  be  obtained  of  a  gardener  or  florist,  in  a  beaker  or  jar  of 

water.1    The  jar  should 

0  p>       . ^ p'  o  be  as  thin  and  trans- 

parent as  possible,  and 
it  is  well  to  get  a  flat- 
sided  rather  than  a 
cylindrical  one.  Leave 
the  jar  of  cuttings  in 
a  sunny,  warm  place. 
As  soon  as  roots  have 
developed  at  the  nodes 
and  reached  the  length 
of  three-quarters  of  an 
inch  or  more,  arrange 
a  microscope  in  a  hori- 
zontal position  (see 
Handbook'),  and  exam- 
ine the  tip  and  adjacent 
portion  of  one  of  the 
young  roots  with  a 
power  of  from  twelve 
to  twenty  diameters. 
Note: 

(a)  The  root-cap, 
of     loosely 
attached  cells. 
(6)  The  central 
cylinder. 


FIG.  20.  —  Lengthwise    Section    (somewhat    diagram- 
matic) through  Boot-Tip  of  Indian  Corn,    x  about  130. 

W,  root-cap  ;  i,  younger  part  of  cap  ;  z,  dead  cells  sepa- 
rating from  cap  ;  s,  growing  point ;  o,  epidermis  ;  p't 
intermediate  layer  between  epidermis  and  central 
cylinder  ;  p,  central  cylinder  ;  d,  layer  from  which 
the  root-cap  originates. 


1  If  the  tradescantia  or  Zebrina  cannot  be  obtained,  roots  of  seedlings  of 
oats,  wheat,  or  barley,  or  of  red-clover  seedlings  raised  in  a  large  covered  cell 
on  a  microscope  slide,  may  be  used. 


ROOTS  43 

(c)  The  cortical  portion,  a  tubular  part  enclosing  the  solid 

central  cylinder. 

(d)  The  root-hairs,  wnich  cover  some  parts  of  the  outer  layer  of 

the  cortical  portion  very  thickly.  Observe  particularly 
how  far  toward  the  tip  of  the  root  the  root-hairs  extend, 
and  where  the  youngest  ones  are  found. 

Make  a  drawing  to  illustrate  all  the  points  above  suggested 
(a,  b,  c,  d).  Compare  your  drawing  with  Fig.  20.  Make  a  careful 
study  of  longitudinal  sections  through  the  centers  of  the  tips  of  very 
young  roots  of  the  hyacinth  or  the  Chinese  sacred  lily.  Sketch 
one  section  and  compare  the  sketch  with  Fig.  20. 

Make  a  study  of  the  roots  of  any  of  the  common  duckweeds, 
growing  in  nutrient  solution  in  a  jar  of  water  under  a  bell-glass,  and 
note  the  curious  root-pockets  which  here  take  the  place  of  root-caps. 

54.  Details  of  Root-Structure.  —  The  plan  on  which  the 
young  root  is  built  has  been  outlined  in  Sect.  53.  A  few 
further  particulars  are  necessary  to  an  understanding  of 
how  the  root  does  its  work.  On  examining  Fig.  21  the 
cylinders  of  which  the  root  is  made  up  are  easily  dis- 
tinguished, and  the  main  constituent  parts  of  each  can  be 
made  out  without  much  trouble.  The  epidermis-cells  are 
seen  to  be  somewhat  brick-shaped,  many  of  them  provided 
with  extensions  into  root-hairs.  Inside  the  epidermis  lie 
several  layers  of  rather  globular,  thin-walled  cells,  and 
inside  these  a  boundary  layer  between  the  cortical  or  bark 
portion  of  the  root  and  the  central  cylinder.  This  latter 
region  is  especially  marked  by  the  presence  of  certain 
groups  of  cells,  shown  at  w  and  d  and  at  5,  the  two 
former  serving  as  channels  for  air  and  water,  the  latter 
(and  w  also)  giving  toughness  to  the  root. 

Roots  of  shrubs  and  trees  more  than  a  year  old  will 
be  found  to  have  increased  in  thickness  by  the  process 


44 


FOUNDATIONS   OF  BOTANY 


described  in  Sect.  106,  and  a  section  may  look  quite  unlike 
the  young  root-section  shown  in  Fig.  21. 

55.  Examination  of  the  Root  of  a  Shrub  or  Tree.  —  Cut  thin 
transverse  sections  of  large  and  small  roots  of  any  hardwood  tree  l 
and  examine  them  first  with  a  low  power  of  the  microscope,  as  a 
two-inch  objective,  to  get  the  general  disposition  of  -the  parts,  then 

with  a  higher  power, 
as  the  half-inch  or 
quarter-inch,  for  de- 
tails. With  the  low 
power,  note: 

(a)  The  brown 
layer  of  outer  bark. 
(6)  The  paler  layer 
within  this. 

(c)  The  woody  cyl- 
inder which  forms 
the  central  portion  of 
the  root. 

The  distinction  be- 
tween (b)  and  (c)  is 
more  evident  when 
the  section  has  been 
exposed  to  the  air  for 
a  few  minutes  and 
h,  root-hairs  with  adhering  bits  of  sand  ;  e,  epidermis  ;  changed  somewhat  in 

color.  It  is  a  good 
plan  to  look  with  the 
low  power  first  at  a  thick  section,  viewed  as  an  opaque  object,  and 
then  at  a  very  thin  one  mounted  in  water  or  glycerine,  and  viewed  as 
a  transparent  object. 

Observe  the  cut-off  ends  of  the  ducts,  or  vessels,  which  serve  as 
passages  for  air  and  water  to  travel  through ;  these  appear  as  holes  in 
the  section,  and  are  much  more  abundant  relatively  in  the  young 

1  Young  suckers  of  cherry,  apple,  etc.,  which  may  be  pulled  up  by  the 
roots,  will  afford  excellent  material. 


FIG.  21.  — Much  Magnified  Cross-Section  of  a 
Very  Young  Dicotyledonous  Root. 


s,  thin-walled,  nearly  globular  cells  of  bark  ;  b,  hard 
bast ;  c,  cambium  ;  w,  wood-cells  ;  d,  ducts. 


ROOTS  45 

than  in  the  older  and  larger  portions  of  the  root.  Sketch  one  section 
of  each  kind. 

Examine  with  a  higher  power  (100  to  200  diameters),  and  note  the 
ends  of  the  thick-walled  wood-cells.  Compare  these  with  Fig.  72. 

Notice  the  many  thinner-walled  cells  composing  stripes  radiating 
away  from  the  center  of  the  root.  These  bands  are  the  medullary 
rays,  whose  mode  of  origin  is  shown  in  Fig.  68.  Moisten  some  of 
the  sections  with  iodine  solution,1  and  note  where  the  blue  color 
shows  the  presence  of  starch.  Split  some  portions  of  the  root  through 
the  middle,  cut  thin  sections  from  the  split  surface,  and  examine  with 
the  high  power  some  unstained  and  some  stained  with  iodine. 

Notice  the  appearance  of  the  wood-cells  and  the  ducts  as  seen  in 
these  sections,  and  compare  with  Fig.  58. 2 

56.  Structure  and  Contents  of  a  Fleshy  Root.  —  In  some 
fleshy  roots,  such  as  the  beet,  the  morphology  of  the  parts 
is  rather  puzzling,  since  they  form  many  layers  of  tissue 
in  a  single  season,  showing  on  the  cross-section  of  the  root 
a  series  of  layers  which  look  a  little  like  the  annual  rings 
of  trees. 

The  structure  of  the  turnip,  radish,  carrot,  and  parsnip 
is  simpler. 

Cut  a  parsnip  across  a  good  deal  below  the  middle,  and  stand  the 
cut  end  in  eosin  solution  for  twenty-four  hours. 

Then  examine  by  slicing  off  successive  portions  from  the  upper 
end.  Sketch  some  of  the  sections  thus  made.  Cut  one  parsnip 
lengthwise  and  sketch  the  section  obtained.  In  what  portion  of  the 
root  did  the  colored  liquid  rise  most  readily  ?  The  ring  of  red  marks 
the  boundary  between  the  cortical  portion  and  the  central  cylinder. 
To  which  does  the  main  bulk  of  the  parsnip  belong?  Cut  thin 
ta-ansverse  sections  from  an  ink-stained  parsnip  and  notice  how  the 
medullary  rays  run  out  into  the  cortical  portion,  and  in  those  sections 

1  If  the  roots  are  in  their  winter  condition. 

2  The  examination  of  the  minute  structure  of  the  root  is  purposely  made 
very  hasty,  since  the  detailed  study  of  the  structural  elements  can  be  made  to 
better  advantage  in  the  stem. 


46  FOUNDATIONS   OF  BOTANY 

that  show  it,  find  out  where  the  secondary  roots  arise.  If  possible, 
peel  off  the  cortical  portion  from  one  stained  root  and  leave  the  cen- 
tral cylinder  with  the  secondary  roots  attached.  Stain  one  section 
with  iodine,  and  sketch  it.  Where  is  the  starch  of  this  root  mainly 
stored  ? 

Test  some  bits  of  parsnip  for  proteids,  by  boiling  them  for  a 
minute  or  two  with  strong  nitric  acid. 

What  kind  of  plant-food  does  the  taste  of  cooked  parsnips  show 
them  to  contain  ?  [On  no  account  taste  the  bits  which  have  been 
boiled  in  the  poisonous  nitric  acid.] 

57.  Storage  in  Other  Roots.  -  -  The  parsnip  is  by  no 
means  a  remarkable  plant  in  its  capacity  for  root-storage. 
The  roots  of  the  yam  and  the  sweet  potato  contain  a  good 
deal  of  sugar  and  much  more  starch  than  is  found  in  the 
parsnip.  Beet-roots  contain  so  much  sugar  that  a  large 
part  of  the  sugar  supply  of  Europe  and  an  increasing 
portion  of  our  own  supply  is  obtained  from  them.  Often- 
times the  bulk  of  a  fleshy  root  is  exceedingly  large  as 
compared  with  that  of  the  parts  of  the  plant  above 
ground. 

The  South  African  plant  (Harp agopliy turn,  Chapter 
XXIV)  is  a  good  example  of  this,  and  another  instance 
is  that  of  a  plant,1  related  to  the  morning-glory  and  the 
sweet  potato,  found  in  the  southeastern  United  States, 
which  has  a  root  of  forty  or  fifty  pounds  weight. 

Not  infrequently  roots  have  a  bitter  or  nauseous  taste, 
as  in  the  case  of  the  chicory,  the  dandelion,  and  the 
rhubarb,  and  a  good  many,  like  the  monkshood,  the  yellow 
jasmine,  and  the  pinkroot,  are  poisonous.  Can  you  give 
any  reason  why  the  plant  may  be  benefited  by  the  disgust- 
ing taste  or  poisonous  nature  of  its  roots  ? 

1  Ipomcea  Jalapa. 


ROOTS 


47 


58.  Use  of  the   Food  stored  in   Fleshy  Roots.  —  The 
parsnip,  beet,  carrot,  and  turnip  are  biennial  plants;  that 
is,  they  do  not  produce  seed  until  the  second  summer  or 
fall  after  they  are  planted. 

The  first  season's  work  consists  mainly  in  producing  the 
food  which  is  stored  in  the  roots.  To  such  storage  is 
due  their  characteristic  fleshy  appear- 
ance. If  this  root  is  planted  in  the 
following  spring,  it  feeds  the  rapidly 
growing  stem  which  proceeds  from  the 
bud  at  its  summit,  and  an  abundant 
crop  of  flowers  and  seed  soon  follows; 
while  the  root,  if  examined  in  late  sum- 
mer, will  be  found  to  be  withered,  with 
its  store  of  reserve  material  quite  ex- 
hausted. 

The  roots  of  the  rhubarb  (Fig.  22), 
the  sweet  potato,  and  of  a  multitude  of 
other  perennials,  or  plants  which  live 
for  many  years,  contain  much  stored  FIG.  22. -Fleshy  Roots 

J     J  of  Garden  Rhubarb. 

plant-food.      Many  such  plants  die  to 

the  ground  at  the  beginning  of  winter, 

and  in  spring  make  a  rapid  growth  from  the  materials  laid 

up  in  the  roots. 

59.  Extent  of  the  Root-System.  —  The  total  length  of 
the  roots  of  ordinary  plants  is  much  greater  than  is  usually 
supposed.     They  are  so  closely  packed  in  the  earth  that 
only  a  few  of  the  roots  are  seen  at  a  time  during  the 
process  of  transplanting,  and  when  a  plant  is  pulled  or  dug 
up  in  the  ordinary  way,  a  large  part  of  the  whole  mass  of 
roots  is  broken  off  and  left  behind.     A  few  plants  have 


(About  one-fifteenth 
natural  size.) 


48  FOUNDATIONS   OF  BOTANY 

been  carefully  studied  to  ascertain  the  total  weight  and 
length  of  the  roots.  Those  of  winter  wheat  have  been 
found  to  extend  to  a  depth  of  seven  feet.  By  weighing 
the  whole  root-system  of  a  plant  and  then  weighing  a 
known  length  of  a  root  of  average  diameter,  the  total 
length  of  the  roots  may  be  estimated.  In  this  way  the 
roots  of  an  oat  plant  have  been  calculated  to  measure 
about  154  feet;  that  is,  all  the  roots,  if  cut  off  and  strung 
together  end  to  end,  would  reach  that  distance. 

Single  roots  of  large  trees  often  extend  horizontally  to 
great  distances,  but  it  is  not  often  possible  readily  to  trace 
the  entire  depth  to  which  they  extend.  One  of  the  most 
notable  examples  of  an  enormously  developed  root-system 
is  found  in  the  mesquite  of  the  far  Southwest  and  Mexico. 
When  this  plant  grows  as  a  shrub,  reaching  the  height, 
even  in  old  age,  of  only  two  or  three  feet,  it  is  because  the 
water  supply  in  the  soil  is  very  scanty.  In  such  cases 
the  roots  extend  down  to  a  depth  of  sixty  feet  or  more, 
until  they  reach  water,  and  the  Mexican  farmers  in  dig- 
ging wells  follow  these  roots  as  guides.  Where  water  is 
more  plenty,  the  mesquite  forms  a  good-sized  tree,  with 
much  less  remarkably  developed  roots. 

60.  The  Absorbing  Surface  of  Roots.  —  Such  aerial  roots 
as  are  shown  in  Fig.  13  are  usually  covered  with  a  spongy 
absorbent  layer,  by  means  of  which  they  retain  large 
quantities  of  the  water  which  trickles  down  them  during 
rain-storms.  '  This  water  they  afterwards  gradually  give 
up  to  the  plant.  Most  water-roots  (not  however  those  of 
tradescantia)  have  no  special  arrangement  for  absorbing 
water  except  through  the  general  surface  of  their  epidermis. 
But  some  water-roots  and  most  soil-roots  take  in  water 


ROOTS 


49 


mainly  through  the  root-hairs.  These  are  delicate,  hair- 
like  outgrowths  from  the  epidermis  of  the  root.  They 
are,  as  seen  in  Fig.  11,  thin-walled  tubes,  of  nearly  uniform 
diameter,  closed  at  the  outer  end  and  opening  at  the  inner 
end  into  the  epidermis-cell  from  which  they 
spring.  The  relation  of  each  hair  to  the 
epidermis-cell  is  still  better  shown  in  Fig. 
23,  which  represents  a  very  young  root- 
hair  and  a  considerably  older  one. 

61.  Absorption  of  Water  by  Roots.  - 
Many  experiments  on  the 
cultivation  of  corn,  wheat, 
oats,  beans,  peas,  and  other 
familiar  plants  in  water  have 
proved  that  some  plants,  at 
any  rate,  can  thrive  very 
well  on  ordinary  lake,  river, 
or  well  water,  together  with 
the  food  which  they  absorb 
from  the  air  (Chapter  XII). 
Just  how  much  water  some 
kinds  of  plants  give  off  (and 
therefore  absorb)  per  day 
will  be  discussed  when  the 
uses  of  the  leaf  are  studied. 
For  the  present  it  is  suffi- 
cient to  state  that  even  an 
annual  plant  during  its  lifetime  absorbs  through  the  roots 
very  many  times  its  own  weight  of  water.  Grasses  have  been 
known  to  take  in  their  weight  of  water  in  every  twenty- 
four  hours  of  warm,  dry  weather.  This  absorption  takes 


A  B 

FIG.  23. 

A,  a  very  youug  root-hair ;  B,  a  much 
older  one  (both  greatly  magnified). 
e,  cells  of  the  epidermis  of  the  root ; 
n,  nucleus ;  s,  watery  cell-sap ;  p, 
thicker  protoplasm,  lining  the  cell- 
wall. 


50  FOUNDATIONS   OF   BOTANY 

place  mainly  through  the  root-hairs,  which  the  student  has 
examined  as  they  occur  in  the  seedling  plant,  and  which 
are  found  thickly  clothing  the  younger  and  more  rapidly 
growing  parts  of  the  roots  of  mature  plants.  Some  idea 
of  their  abundance  may  be  gathered  from  the  fact  that  on 
a  rootlet  of  corn  grown  in  a  damp  atmosphere,  and  about 
one-seventeenth  of  an  inch  in  diameter,  480  root-hairs  have 
been  counted  on  each  hundredth  of  an  inch  of  root.  The 
walls  of  the  root-hairs  are  extremely  thin,  and  they  have 
no  holes  or  pores  visible  under  even  the  highest  power 
of  the  microscope,  yet  the  water  of  the  soil  penetrates 
very  rapidly  to  the  interior  of  the  root-hairs.  The 
soil-water  brings  with  it  all  the  substances  which  it  can 
dissolve  from  the  earth  about  the  plant ;  and  the  close- 
ness with  which  the  root-hairs  cling  to  the  particles  of  soilv 
as  shown  in  Figs.  11  and  21,  must  cause  the  water  which 
is  absorbed  to  contain  more  foreign  matter  than  under., 
ground  water  in  general  does,  particularly  since  the  roots 
give  off  enough  weak  acid  from  their  surface  to  corrode 
the  surface  of  stones  which  they  enfold  or  cover. 

62.  Osmosis.  —  The  process  by  which  two  liquids  sep- 
arated by  membranes  pass  through  the  latter  and  mingle, 
as  soil-water  does  with  the  liquid  contents  of  root-hairs,  is 
called  osmosis. 

It  is  readily  demonstrated  by  experiments  with  thin 
animal  or  vegetable  membranes. 

EXPERIMENT   XY 

Osmosis  as  shown  in  an  Egg.  —  Cement  to  the  smaller  end  of  an  egg 
a  bit  of  glass  tubing  about  six  inches  long  and  about  three-sixteenths 
of  an  inch  inside  diameter.  Sealing-wax  or  a  mixture  of  equal  parts 
of  beeswax  and  resin  melted  together  will  serve  for  a  cement. 


ROOTS 


51 


Chip  away  part  of  the  shell  from  the  larger  end  of  the  egg,  place 
it  in  a  wide-mouthed  bottle  or  a  small  beaker  full  of  water,  as  shown 
in  Fig.  24,  then  very  cautiously  pierce  a  hole  through  the  upper  end 
of  the  eggshell  by  pushing  a  knitting-needle  or  wire  down  through 
the  glass  tube. 

Watch  the  apparatus  for  some  hours  and  note  any  change  in  the 
contents  of  the  tube.1  Explain. 

The  rise  of  liquid  in  the  tube  is  evidently  due  to  water  making 
its  way  through  the  thin  membrane  which  lines  the  eggshell, 
although  this  membrane  contains  no  pores  visible  even  under  the 
microscope. 

EXPERIMENT   XVI 

Result  of  placing  Sugar  on  a  Begonia  Leaf.  —  Place  a  little  pow- 
dered sugar  on  the  upper  surface  of  a  thick  begonia  leaf  under  a  small 
bell-glass.  Put  another  por- 
tion of  sugar  or  a  bit  of  paper 
alongside  the  leaf.  Watch  for 
several  days.  Explain  results. 
The  upper  surface  of  this  leaf 
contains  no  pores,  even  of 
microscopic  size. 

63.  Inequality  of  Os- 
motic Exchange.  -  -  The 
nature  of  the  two  liquids 
separated  by  any  given 
membrane  determines  in 
which  direction  the 
greater  flow  shall  take 
place. 

If  one  of  the  liquids  is 
pure  water  and  the  other 


FIG.  24.  —Egg  on  Beaker  of  Water, 
to  show  Osmosis. 


1  Testing  the  contents  of  the  beaker  with  nitrate  of  silver  solution  will 
then  show  the  presence  of  more  common  salt  than  is  found  in  ordinary  water. 
Explain. 


52  FOUNDATIONS   OF   BOTANY 

is  water  containing  solid  substances  dissolved  in  it,  the 
greater  flow  of  liquid  will  be  away  from  the  pure  water 
into  the  solution,  and  the  stronger  or  denser  the  latter,  the 
more  unequal  will  be  the  flow.  This  principle  is  well  illus- 
trated by  the  egg-osmosis  experiment.  Another  important 
principle  is  that  substances  which  readily  crystallize  and 
are  easily  soluble,  like  salt  or  sugar,  pass  rapidly  through 
membranes,  while  jelly-like  substances,  like  white  of  egg, 
can  hardly  pass  through  them  at  all. 

64,  Study  of  Osmotic  Action  of  Living  Protoplasm ; 
Plasmolysis.  —  The  obvious  parts  of  most  living  and  grow- 
ing plant-cells  are  a  cell-wall,  which  is  a  skin  or  enclosure 
made  of  cellulose,  and  the  living,  active  cell-contents  or 
protoplasm.  Every  one  is  familiar  with  cellulose  in  vari- 
ous forms,  one  of  the  best  examples  being  that  afforded  by 
clean  cotton.  It  is  a  tough,  white  or  colorless  substance, 
chemically  rather  inactive.  Protoplasm  is  a  substance  which 
differs  greatly  in  its  appearance  and  properties  under  differ- 
ent circumstances.  It  is  of  a  very  complex  nature,  so  far  as 
its  chemical  composition  is  concerned,  belonging  to  the  group 
of  proteids  and  therefore  containing  not  only  the  elements 
carbon,  hydrogen,  and  oxygen,  common  to  most  organic 
substances,  but  nitrogen  in  addition.  The  protoplasm  in 
a  living  cell  often  consists  of  several  kinds  of  material ;  for 
instance,  a  rather  opaque  portion  called  the  nucleus,  and  a 
more  or  less  liquid  portion  lining  the  cell-walls  and  extend- 
ing inward  in  strands  to  the  nucleus  (Fig.  126).  Often,  in 
living  and  active  cells,  the  spaces  left  between  strands  and 
lining  are  filled  with  a  watery  liquid  called  the  cell-sap. 

The  action  of  the  protoplasm  in  controlling  osmosis  is 
well  shown  by  the  process  known  as  plasmolysis. 


ROOTS  53 

Put  some  living  threads  of  pond-scum  (Spiroyyra)  (Chapter  XX) 
into  a  4  per  cent  solution  of  glycerine  in  water,  a  16  per  cent  solution 
of  cane  sugar,  or  (for  quick  results)  a  2  per  cent  solution  of  common 
salt.1  Any  one  of  these  solutions  is  much  denser  than  the  cell-sap 
inside  the  cells  of  the  pond-scum,  and  therefore  the  watery  part  of 
the  cell-contents  will  be  drawn  out  of  the  interior  of  the  cell  and 
the  protoplasmic  lining  will  collapse,  receding  from  the  cell-wall. 
The  cell-contents  are  then  said  to  be  plasmolyzed .  Sketch  several 
cells  in  this  condition.  Remove  the  filaments  of  Spirogyra  and 
place  them  in  fresh  water.  How  do  they  now  behave  ?  Explain. 
Repeat  the  plasmolyzing  operation  with  another  set  of  cells  which 
have  first  been  killed  by  soaking  them  for  five  minutes  in  a  mixture 
of  equal  quantities  of  acetic  acid,  three  parts  to  1000  of  water,  and 
chromic  acid,  seven  parts  to  1000  of  water.  The  pond-scum  threads 
before  being  transferred  from  the  killing  solution  into  the  plas- 
molyzing solution  should  be  rinsed  with  a  little  clear  water.  Note 
how  the  cells  now  behave.  How  is  it  shown  that  they  have  lost 
their  power  of  causing  a  liquid  to  be  transferred  mainly  or  wholly 
in  one  direction?  Why  do  frozen  or  boiled  slices  of  a  red  beet 
color  water  in  which  they  are  placed,  while  fresh  slices  do  not? 

65.  Osmosis  in  Root-Hairs.  —  The  soil-water  (practically 
identical  with  ordinary  spring  or  well  water)  is  separated 
from  the  more  or  less  sugary  or  mucilaginous  sap  inside 
of  the  root-hairs  only  by  their  delicate  cell-walls,  lined 
with  a  thin  layer  of  protoplasm.  This  soil- water  will  pass 
rapidly  into  the  plant,  while  very  little  of  the  sap  will 
come  out.  The  selective  action,  which  causes  the  flow  of 
liquid  through  the  root-hairs  to  be  almost  wholly  inward, 
is  due  to  the  living  layer  of  protoplasm  (Chapter  XII), 
which  covers  the  inner  surface  of  the  cell-wall  of  the  root- 
hair.  When  the  student  has  learned  how  active  a  sub- 
stance protoplasm  often  shows  itself  to  be,  he  will  not  be 
astonished  to  find  it  behaving  almost  as  though  it  were 

1  This  should  be  done  as  a  demonstration  by  the  teacher. 


54  FOUNDATIONS   OF   BOTANY 

possessed  of  intelligence  and  will.  Plants  of  two  different 
species,  both  growing  in  the  same  soil,  usually  take  from 
it  very  various  amounts  or  kinds  of  mineral  matter.  For 
instance,  barley  plants  in  flower  and  red-clover  plants  in 
flower  contain  about  the  same  proportion  of  mineral  mat- 
ter (left  as  ashes  after  burning).  But  the  clover  contains 
5|  times  as  much  lime  as  the  barley,  and  the  latter  contains 
about  eighteen  times  as  much  silica  as  the  clover.  This 
difference  must  be  due  to  the  selective  action  of  the  proto- 
plasm in  the  absorbing  cells  of  the  roots.  Traveling  by 
osmotic  action  from  cell  to  cell,  a  current  of  water  derived 
from  the  root-hairs  is  forced  up  through  the  roots  and  into 
the  stem,  just  as  the  contents  of  the  egg  was  forced  up 
into  the  tube  shown  in  Fig.  24. 

66.  Root-Pressure.  --  The  force  .with  which  the  upward- 
flowing  current  of  water  presses  may  be  estimated  by 
attaching  a  mercury  gauge  to  the  root  of  a  tree  or  the 
stem  of  a  small  sapling.  This  is  best  done  in  early  spring 
after  the  thawing  of  the  ground,  but  before  the  leaves 
have  appeared.  The  experiment  may  also  be  performed 
indoors  upon  almost  any  plant  with  a  moderately  firm 
stem,  through  which  the  water  from  the  soil  rises  freely. 
A  dahlia  plant  or  a  tomato  plant  answers  well,  though  the 
root-pressure  from  one  of  these  will  not  be  nearly  as  great 
as  that  from  a  larger  shrub  or  a  tree  growing  out  of  doors. 
In  Fig.  25  the  apparatus  is  shown  attached  to  the  stem  of 
a  dahlia.  The  difference  of  level  of  the  mercury  in  the 
bent  tube  serves  to  measure  the  root-pressure.  For  every 
foot  of  difference  in  level  there  must  be  a  pressure  of 
nearly  six  pounds  per  square  inch  on  the  stump  at  the 
base  of  the  tube  T.1 

1  See  Handbook. 


ROOTS 


A  black-birch  root  tested  in  this  way  at  the  end  of 
April  has  given  a  root-pressure  of  thhty-seven  pounds  to 
the  square  inch.  This  would  sustain  a  column  of  water 
about  eighty-six  feet  high. 

67.  Root-Absorption  and 
Temperature  of  Soil.  —  It 
would  not  be  remarkable  if 
the  temperature  of  roots  and 
the  earth  about  them  had 
something  to  do  with  the 
rate  at  which  they  absorb 
water,  since  this  absorption 
depends  on  the  living  proto- 
plasm of  the  root-hairs  (see 
Sects.  64,  65).  An  experi- 
ment will  serve  to  throw 
some  light  on  this  question. 


EXPERIMENT   XVII 


-I-/' 


FIG.  25.  —  Apparatus  to  Measure 
Boot-Pressure. 


T,  large  tube  fastened  to  the  stump  of 
the  dahlia  stem  by  a  rubber  tube  ; 
rr,  rubber  stoppers ;  t,  bent  tube 
containing  mercury  ;  1 1',  upper  and 
lower  level  of  mercury  in  T. 


Effect  of  Temperature  on  Absorp- 
tion of  Water  by  Roots.  —  Trans- 
plant a  tobacco  seedling  about  four 
inches  high  into  rich  earth  con- 
tained in  a  narrow,  tall  beaker  or 
very  large  test-tube  (not  less  than 
1£  inch  in  diameter  and  six  inches  high).  When  the  plant  has  begun 
to  grow  again  freely,  in  a  warm,  sunny  room,  insert  a  chemical  ther- 
mometer into  the  earth,  best  by  making  a  hole  with  a  sharp  round 
stick,  pushed  nearly  to  the  bottom  of  the  tube,  and  then  putting  the 
thermometer  in  the  place  of  the  stick.  Water  the  plant  well,  then 
set  the  tube  in  a  jar  of  pounded  ice  which  reaches  nearly  to  the 
top  of  the  tube.  Note  the  temperature  of  the  earth  just  before 
placing  it  in  the  ice.  Observe  whether  the  leaves  of  the  selling  wilt, 


56  FOUNDATIONS   OF   BOTANY 

and,  if  so,  at  what  temperature  the  wilting  begins.  Finally,  remove 
the  tube  from  the  ice  and  place  it  in  warm  water  (about  80°). 
Observe  the  effect  and  note  the  temperature  at  which  the  plant, 
if  wilted,  begins  to  revive.  Find  an  average  between  the  wilting 
temperature  and  the  reviving  temperature.  For  what  does  this 
average  stand? 

68.  Movements  of  Young  Roots.  —  The  fact  that  roots 
usually  grow  downward  is  so  familiar  that  we  do  not 
generally  think  of  it  as  a  thing  that  needs  discussion  or 
explanation.  Since  they  are  pretty  flexible,  it  may  seem 
as  though  young  and  slender  roots  merely  hung  down 
by  their  own  weight,  like  so  many  bits  of  wet  cotton 
twine.  But  a  very  little  experimenting  will  answer  the 
question  whether  this  is  really  the  case. 

EXPERIMENT   XVIII 

Do  all  Parts  of  the  Root  of  the  Windsor  Bean  Seedling  bend  down- 
ward alike?  —  Fasten  some  sprouting  Windsor  beans  with  roots 
about  an  inch  in  length  to  the  edges  of  a  disk  of  pine  wood  or 
other  soft  wood  in  a  soup-plate  nearly  full  of  water  and  cover  them 
with  a  low  bell-jar.  Pins  run  through  the  cotyledons,  as  in  Fig.  26, 
will  hold  the  beans  in  place.  When  the  roots  have  begun  to  point 
downward  strongly,  turn  most  of  the  beans  upside  down  and  pin 
them  in  the  reversed  position.  If  you  choose,  after  a  few  days 
reverse  them  again.  Make  sketches  of  the  various  forms  that  the 
roots  assume  and  discuss  these. 

EXPERIMENT   XIX 

Does  the  Windsor  Bean  Root-Tip  press  downward  with  a  Force 
greater  than  its  Own  Weight  ?  —  Arrange  a  sprouted  bean  as  shown 
in  Fig.  26,  selecting  one  that  has  a  root  about  twice  as  long  as  the 
diameter  of  the  bean  and  that  has  grown  out  horizontally,  having 
been  sprouted  on  a  sheet  of  wet  blotting  paper.  The  bean  is  pinned 


ROOTS 


57 


to  a  cork  that  is  fastened  with  beeswax  and  resin  mixture  to  the 
side  of  a  little  trough  or  pan  of  glass  or  glazed  earthenware.  The 
pan  is  filled  half  an  inch  or  more  with  mercury,  and  on  top  of 
the  mercury  is  a  layer 
of  water.  The  whole 
is  closely  covered  by 
a  large  tumbler  or  a 
bell-glass.  Allow  the 
apparatus  to  stand  un- 
til the  root  has  forced 
its  way  down  into  the 
mercury.  Then  run  a 
slender  needle  into  the 
root  'where  it  enters 


FIG.  26.  —A  Sprouting  Windsor  Bean  pushing  its 
Hoot-Tip  into  Mercury. 


s,  seed  ;  r,  root ;  w,  layer  of  water  ;  m,  mercury, 
the  mercury  (to  mark 

the  exact  level),  withdraw  the  root,  and  measure  the  length  of 
the  part  submerged  in  mercury.  To  see  whether  this  part  would 
have  stayed  under  by  virtue  of  its  own  weight,  cut  it  off  and  lay 
it  on  the  mercury.  Push  it  under  with  a  pair  of  steel  forceps  and 
then  let  go  of  it.  What  does  it  do  ? 

69.  Discussion  of  Exp.  XIX.  —  By  comparing  the  weights 
of  equal  bulks  of  mercury  and  Windsor  bean  roots,  it  is 
found  that  the  mercury  is  about  fourteen  times  as  heavy 
as  the  substance  of  the  roots.     Evidently,  then,  the  sub- 
merged part  of  the  root  must  have  been  held  under  by 
a  force  about  fourteen  times  its  own  weight.     Making  fine 
equidistant  cross-marks  with  ink  along  the  upper  and  the 
lower  surface  o'f  a  root  that  is  about  to  bend  downward  at 
the  tip,  readily  shows  that  those  of  the  upper  series  soon 
come  to  be  farther  apart,  —  in  other  words,  that  the. root  is 
forced  to  bend  downward  by  the  more  rapid  growth  of  its 
upper  as  compared  with  its  under  surface. 

70.  Geotropism.  —  The  property  which  plants  or  their 
organs   manifest,   of   assuming  a  definite  direction  with 


68 


FOUNDATIONS   OF  BOTANY 


reference  to  gravity,1  is  called  geotropism.  When,  as  in 
the  case  of  the  primary  root,  the  effect  of  gravity  is  to 
make  the  part  if  unobstructed  turn  or  move  downward, 
we  say  that  the  geotropism  is  positive.  If  the  tendency  is 
to  produce  upward  movement,  we  say  that  the  geotropism 
is  negative;  if  horizontal  movement,  that  it  is  lateral.  It 
was  stated  in  the  preceding  section  that  the  direct  cause 
of  the  downward  extension  of  roots  is  unequal  growth. 
We  might  easily  suppose  that  this  unequal  growth  is  not 
due  to  gravity,  but  to  some  other  cause.  To  test  this  sup- 
position, the  simplest  plan  (if  it  could  be  carried  out)  would 
be  to  remove  the  plants  studied  to  some  distant  re*gion 
where  gravity  does  not  exist.  This  of  course  cannot  be 

done,  but  we  can  easily  turn  a 
young  seedling  over  and  over 
so  that  gravity  will  act  on  it 
now  in  one  direction,  now  in 
another,  and  so  leave  no  more 
impression  than  if  it  did  not  act 
at  all  (Exp.  XX).  Or  we  can 
whirl  a  plant  so  fast  that  not 
only  is  gravity  done  away  with, 

FiG.27.-sproUtingpeas,ontheDisk  but  another  force  is  introduced 
of  a  rapidly  whirling  ciinostat.      in  its  place.    If  a  vertical  wheel, 

like  a  carriage  wheel,  were  pro- 
vided with  a  few  loosely  fitting 
iron  rings  strung  on  the  spokes, 
when  the  wheel  was  revolved  rapidly  the  rings  would  all 
fly  out  to  the  rim  of  the  wheel.  So  in  Fig.  27  it  will  be 


The  youngest  portions  of  the  roots 
all  point  directly  away  from  the 
axis  about  which  they  were  re- 
volved. 


1  Gravity  means  the  pull  which  the  earth  exerts  upon  all  objects  on  or 
near  its  surface. 


ROOTS  59 

noticed  that  the  growing  tips  of  the  roots  of  the  sprouting 
peas  point  almost  directly  outward  from  the  center  of  the 
disk  on  which  the  seedlings  are  fastened.  Explain  the  differ- 
ence between  this  result  and  that  obtained  in  Exp.  XX. 

EXPERIMENT    XX 

How  do  Primary  Roots  point  when  uninfluenced  by  Gravity  ?  Pin 
some  soaked  Windsor  beans  to  a  large  flat  cork,  cover  them  with 
thoroughly  moistened  chopped  peat-moss,  and  cover  this  with  a  thin 
glass  crystallizing  dish.  Set  the  cork  on  edge.  Prepare  another 
cork  in  the  same  way,  attach  it  to  a  cliuostat,  and  keep  it  slowly 
revolving  in  a  vertical  position  for  from  three  to  five  days.  Com- 
pare the  directions  taken  by  the  roots  on  the  stationary  and  on  the 
revolving  cork.1 

71.  Direction  taken  by  Secondary  Roots.  —  As  the  stu- 
dent has  already  noticed  in  the  seedlings  which  he  has 
studied,  the  branches  of  the  primary  root  usually  make  a 
considerable  angle  with  it  (Fig.  2).     Often  they  ran  out 
for  long  distances  almost  horizontally.     This  is  especially 
common  in  the  roots  of  forest  trees,  above  all  in  cone- 
bearing  trees,  such  as  pines  and  hemlocks.     This  horizon- 
tal or  nearly  horizontal  position  of  large  secondary  roots 
is  the  most  advantageous  arrangement  to  make  them  use- 
ful in  staying  or  guying  the  stem  above,  to  prevent  it  from 
being  blown  over  by  the  wind. 

72,  Fitness  of  the  Root  for  its  Position  and  Work.  —  The 
distribution  of  material  in  the  woody  roots  of  trees  and 
shrubs  and  their  behavior  in  the  soil  show  many  adapta- 
tions to  the  conditions  by  which  tjie  roots  are  surrounded. 

1  See  Ganong's  Teaching  Botanist,  pp.  182-186,  for  complete  directions. 
The  brief  statement  above  given  is  abstracted  from  that  of  Professor  Ganong. 


60 


FOUNDATIONS   OF   BOTANY 


The  growing  tip  of  the  root,  as  it  pushes  its  way  through 
the  soil,  is  exposed  to  bruises  ;  but  these  are  largely  warded 
off  by  the  root-cap.  The  tip  also  shows  a  remarkable 
sensitiveness  to  contact  with  hard  objects,  so  that  when 
touched  by  one  it  swerves  aside  and  thus  finds  its  way 
downward  by  the  easiest  path.  Roots  with  an  unequal 
water  supply  on  either  side  grow  toward  the  moister  soil. 
Roots  are  very  tough,  because  they  need  to  resist  strong 


FIG.  28.  — Roots  of  a  Western  Hemlock  exposed  by  having  most  of  the  Leaf -Mould 
about  them  burned  away  by  Forest  Fires. 

pulls,  but  not  as  stiff  as  stems  and  branches  of  the  same 
size,  because  they  do  not  need  to  withstand  sidewise  pres- 
sure, acting  from  one  side  only.  The  corky  layer  which 
covers  the  outsides  of  roots  is  remarkable  for  its  power 
of  preventing  evaporation.  It  must  be  of  use  in  retaining 
in  the  root  the  moisture  which  otherwise  might  be  lost 
on  its  way  from  the  deeper  rootlets  (#yhich  are  buried  in 
damp  soil),  through  the  upper  portions  of  the  root-system, 
about  which  the  soil  is  often  very  dry. 


ROOTS 


61 


73.  Propagation  by  Means  of   Roots.  —  Some   familiar 
plants,,  such  as  rose  bushes,  are  usually  grown  from  roots 
or  root-cuttings. 

Bury  a  sweet  potato  or  a  dahlia  root  in  damp  sand,  and  watch 
the  development  of  sprouts  from  adventitious  buds.  One  sweet 
potato  will  produce  several  such  crops  of  sprouts,  and  every  sprout 
may  be  made  to  grow  into  a  new  plant.  It  is  in  this  way  that  the 
crop  is  started  wherever  the  sweet  potato  is  grown  for  the  market. 

74.  Tabular  Review  of  Experiments. 
[Continue  the  table  begun  at  end  of  Chapter  III.] 

75.  Review  Summary  of  Roots. 


Kinds  of  roots  as  regards  origin       .... 

Kinds  as  regards  medium  in  which  they  grow 
Structure  of  root  of  a  tree. 


f  mate  rials. 

Storage  in  roots   

<J  location. 

louses. 

f  apparatus. 

Absorption  of  water  by  roots 

J  amount. 

1  proofs. 

^causes. 

fnature. 

Movements  of  roots  

<  causes. 

louses. 

CHAPTER   V 
STEMS 

76.  What  the  Stem  is The  work  of  taking  in  the  raw 

materials  which  the  plant  makes  into  its  own  food  is  done 
mainly  by  the  roots  and  the  leaves.      These  raw  materials 
are  taken  from  earth,  from  water,  and  from  the  air  (see 
Chapter  XI).     The  stern  is  that  part  or  organ  of  the  plant 
which  serves  to  bring  roots  and  leaves  into  communication 
with  each  other.     In  most  flowering  plants  the  stem  also 
serves  the  important  purpose  of  lifting  the  leaves  up  into 
the  sunlight,  where  alone  they  best  can  do  their  special 
work. 

The  student  has  already,  in  Chapter  III,  learned  some- 
thing of  the  development  of  the  stem  and  the  seedling  ; 
he  has  now  to  study  the  external  appearance  and  internal 
structure  of  the  mature  stem.  Much  in  regard  to  this 
structure  can  conveniently  be  learned*  from  the  examina- 
tion of  twigs  and  branches  of  our  common  forest  trees  in 
their  winter  condition. 

77.  The  Horse-Chestnut  Twig.1  —  Procure  a  twig  of  horse-chest- 
nut eighteen  inches  or  more  in  length.    Make  a  careful  sketch  of  it, 
trying  to  bring  out  the  following  points : 

(1)  The  general  character  of  the  bark. 

1  Where  the  buckeye  is  more  readily  obtained  it  will  do  very  well.  Hick- 
ory twigs  answer  the  same  purpose,  and  the  latter  is  a  more  typical  form, 
having  alternate  buds.  The  magnolia  or  the  tulip  tree  will  do.  The  student 
should  (sooner  or  later)  examine  at  least  one  opposite-  and  one  alternate-leaved 
twig. 

02 


STEMS 


63 


(2)  The  large  horseshoe-shaped  scars  and  the  number  and  posi- 
tion of  the  dots  on  these  scars.     Compare  a  scar  with  the  base  of  a 
leaf-stalk  furnished  by  the  teacher. 

(3)  The  ring  of  narrow  scars  around  the  stem  in  one  or  more 
places,1  and  the  different  appearance  of  the  bark  above  and  below 
such  a  ring.     Compare  these  scars  with  those  left  after  removing  the 
scales  of  a  terminal  bud  and  then  see  Fi<*.  29,  b  sc. 

(4)  The  buds  at  the  upper  margin  of  each  leaf- 
scar  and  the  strong  terminal  bud  at  the  end  of  the 
twig. 

(5)  The  flower-bud  scar,  a  concave  impression, 
to  be  found  in  the  angle  produced  by  the  forking 
of  two  twigs,  which  form,  with  the  branch  from 
which  they  spring,  a  Y-shaped  figure  (see  Fig.  36). 

(6)  (On  a  branch  larger  than  the  twig  handed 
round  for  individual  study)  the  place  of  origin  of 
the  twigs  on  the  branch ;  —  make  a  separate  sketch 
of  this. 

The  portion  of  stem  which  originally  bore  any 
pair  of  leaves  is  called  a  node,  and  the  portions  of 
stem  between  nodes  are  called  internodes. 

Describe  briefly  in  writing  alongside  the  sketches 
any  observed  facts  which  the  drawings  do  not  show. 

If  your  twig  was  a  crooked,  rough-barked,  and 
slow-growing  one,  exchange  it  for  a  smooth,  vig- 

&    FIG.  29. -A  quickly 

orous  one,  and  note  the  differences.  Or  if  you  grown  Twig  of 
sketched  a  quickly  grown  shoot,  exchange  for  one  Cherry,  with  Lat- 
of  the  Other  kind.  eral  and  Terminal 

Buds  in  October. 
Answer  the  following  questions  :  b  sc>  bud.scale  scars. 

(a)  How   many   inches    did    your    twig    grow    A11    above    these 
,      .  scars  is  the  growth 

during  the  last  summer?  of  the  sprhlg  and 


...b  sc 


How  many  in  the  summer  before  ? 

How  do  you  know  ? 

How  many  years  old  is  the  whole  twig  given  you  ? 

(b)  How  were  the  leaves  arranged  on  the  twig? 


summer  of  the 
same  year. 


A.  very  vigorous  shoot  may  not  show  any  tucli  rinjj. 


64  FOUNDATIONS   OF  BOTANY 

How  many  leaves  were  there  ? 

Were  they  all  of  the  same  size  ? 

(c1)  What  has  the  mode  of  branching  to  do  with  the  arrangement 
of  the  leaves  ?  with  the  flower-bud  scars  ? 

(c?)  The  dots  on  the  leaf-scars  mark  the  position  of  the  bundles 
of  ducts  and  wood-cells  which  run  from  the  wood  of  the  branch 
through  the  leaf-stalk  up  into  the  leaf. 

78.  Twig  of  Beech.  —  Sketch  a  vigorous  young  twig  of  beech  (or 
of  hickory,  magnolia,  tulip  tree)  in  its  winter  condition,  noting  par- 
ticularly the  respects  in  which  it  differs  from  the  horse-chestnut. 
Describe  in  writing  any  facts  not  shown  in  the  sketch.     Notice  that 
the  buds  are  not  opposite,  nor  is  the  next  one  above  any  given  bud 
found  directly  above  it,  but  part  way  round  the  stem  from  the  posi- 
tion of  the  first  one.      Ascertain,  by  studying  several  twigs   and 
counting  around,  which  bud  is  above  the  first  and  how  many  turns 
round  the  stem  are  made  in  passing  from  the  first  to  the  one  directly 
above  it. 

Observe  with  especial  care  the  difference  between  the  beech  and 
the  horse-chestnut  in  mode  of  branching,  as  shown  in  a  large  branch 
provided  for  the  study  of  this  feature. 

79,  Relation  of  Leaf -Arrangement  to  Branching.1  —  This 
difference,  referred  to  in  Sect.  78,  depends  on  the  fact  that 
the  leaves  of  the  horse-chestnut  were  arranged  in  pairs,  on 
opposite  sides  of  the  stem,  while  those  of  the  beech  were 
not  in  pairs.     Since  the  buds  are  found  at  the  upper  edges 
of  the  leaf-scars,  and  since  most  of  the  buds  of  the  horse- 
chestnut  and  the  beech  are  leaf-buds  and  destined  to  form 
branches,  the  mode  of  branching  and  ultimately  the  form 

1  The  teacher  in  the  Eastern  and  Middle  States  will  do  well  to  make  constant 
use,  in  the  study  of  branches  and  buds,  of  Miss  Newell's  Outlines  of  Lessons 
in  Botany,  Part  I.  The  student  can  observe  for  himself,  with  a  little  guid- 
ance from  the  teacher,  most  of  the  points  which  Miss  Newell  suggests.  If  the 
supply  of  material  is  abundant,  the  twigs  employed  in  the  lessons  above 
described  need  not  be  used  further,  but  if  material  is  scanty,  the  study  of  buds 
may  at  once  be  taken  up.  (See  also  Bailey's  Lessons  with  Plants,  Part  I.) 


STEMS 


65 


of  the  tree  must  depend  largely  on  the  arrangement  of 

leaves  along  the  stem. 

80.    Opposite  Branching In  trees  the  leaves  and  buds 

of  which  are  opposite,  the  tendency  will  be  to  form  twigs 

in  four  rows  about  at  right  angles 

to  each  other  along  the  sides  of 

the  branch,  as  shown  in  Fig.  30. 
This  arrangement  will  not  USUT 

ally  be  perfectly  carried  out,  since 

some  of  the  buds  may  never  grow, 
or  some  may 
grow  much 
faster  than 
others  and  so 
make  the  plan 
of  branching  less 
evident  than  it 
would  be  if  all 
grew  alike. 

81.    Alternate 
Branching.  — In 

trees  like  the  beech  the  twigs  will  be 
found  to  be  arranged  in  a  more  or  less 
regular  spiral  line  about  the  branch. 
This,  which  is  known  as  the  alternate 
arrangement  (Fig.  31),  is  more  com- 
monly met  with  in  trees  and  shrubs 
than  the  opposite  arrangement.  It  ad- 
mits of  many  varieties,  since  the  spiral 

may  wind  more  or  less  rapidly  round  the  stem.     In  the 

apple,  pear,  cherry,  poplar,  oak,  and  walnut,  one  passes 


FIG.  30.  —  Opposite  Branching 

in  a  very  Young  Sapling 

of  Ash. 


FlG.  31.  — Alternate 
Branching  in  a  very 
Young  Apple  Tree. 


66 


FOUNDATIONS    OF   BOTANY 


i.  32.  —  Excurrent  Trunks  of  Big  Trees 
(Sequoias). 


over  five  spaces  before 
coming  to  a  leaf  which 
is  over  the  first,  and  in 
doing  this  it  is  necessary 
to  make  two  complete 
turns  round  the  stem 
(Fig.  105). 

82,  Growth  of  the  Ter- 
minal Bud.  --In  some 
trees  the  terminal  bud 
from  the  very  outset 
keeps  the  leading  place, 
and  the  result  of  this 
mode  of  growth  is  to 
produce  a  slender,  up- 
right tree,  with  an  excur- 
rent  trunk  like  that  of 
Fig.  32. 

In  such  trees  as  the 
apple  and  many  oaks  the 
terminal  bud  has  no  pre- 
eminence over  others,  and 
the  form  of  the  tree  is 
round-topped  and  spread- 
ing, deliquescent  like  that 
in  Fig.  33. 

Most  of  the  larger  for- 
est trees  are  intermediate 
between  these  extremes. 

Branches  get  their 
characteristics  to  a 


STEMS 


67 


FlG.  33. — All  Ameriuuu  Elm,  with  Deliquescent  Trunk. 

considerable  degree  from  the  relative  importance  of  their 
terminal  buds.  If  these  are  mainly  flower-buds,  as  is  the  case 
in  the  horse-chestnut  and  some  magnolias  (Figs.  35,  36), 


68  FOUNDATIONS   OF   BOTANY 

the  tree  is  characterized  by  frequent  forking,  and  has 
no  long  horizontal  branches. 

If  the  terminal  bud  keeps  the  lead  of  the  lateral  ones, 
but  the  latter  are  numerous  and  most  of  them  grow  into 
slender  twigs,  the  delicate  spray  of  the  elm  and  many 
birches  is  produced  (Fig.  37). 

The  general  effect  of  the  branching  depends  much  upon 
the  angle  which  each  branch  or  twig  forms  with  that  one 
from  which  it  springs.  The  angle  may  be  quite  acute,  as 
in  the  birch  ;  or  more  nearly  a  right  angle,  as  in  the  ash 
(Fig.  30).  The  inclination  of  lateral  branches  is  due  to 
geotropism,  just  as  is  that  of  the  branches  of  primary  roots. 
The  vertically  upward  direction  of  the  shoot  which  grows 
from  the  terminal  bud  is  also  due  to  geotropism. 

This  is  really  only  a  brief  way  of  saying  that  the  grow- 
ing tip  of  the  main  stem  of  the  tree  or  of  any  branch  is 
made  to  take  and  keep  its  proper  direction,  whether  verti- 
cally upward  or  at  whatever  angle  is  desirable  for  the  tree, 
by  the  steering  action  of  gravity.  After  growth  has  ceased 
this  steering  action  can  no  longer  be  exerted,  and  so  a  tree 
that  has  been  bent  over  (as,  for  instance,  by  a  heavy  load 
of  snow)  cannot  right  itself,  unless  it  is  elastic  enough  to 
spring  back  when  the  load  is  removed.  The  tip  of  the 
trunk  and  of  each  branch  can  grow  and  thus  become 
vertical,  but  the  old  wood  cannot  do  so. 

83.  Thorns  as  Branches.  —  In  many  trees  some  branches 
show  a  tendency  to  remain  dwarfish  and  incompletely 
developed.  Such  imperfect  branches  forming  thorns  are 
familiar  in  wild  crab-apple  trees  and  in  the  pear  trees 
which  occur  in  old  pastures  in  the  Northeastern  States.  In 
the  honey  locust  very  formidable  branching  spines  spring 


STK.MS 


69 


from  adventitious  or  dormant  buds  on  the  trunk  or  limbs. 
Such  spines  sometimes  show  their  true  nature  as  branches 
by  bearing  leaves  (Fig.  34). 

84.  Indefinite  Annual  Growth.  —  In  most  of  the  forest 
trees,  and  in  the  larger  shrubs,  the  wood  of  young  branches 
is  matured  and  fully 

developed  during  the  1 

summer.  Protected 
buds  are  formed  on 
the  twigs  of  these 
branches  to  their  very 
tips.  In  other  shrubs 
—  for  example,  in  the 
sumac,  the  raspberry, 
and  blackberry  —  the 
shoots  continue  to 
grow  until  their  soft 
and  immature  tips  are 
killed  by  the  frost. 

Such  a  mode  of  growth  is  called  indefinite 
annual  growth,  to  distinguish  it  from  the 
definite  annual  growth  of  most  trees. 

85.  Trees,  Shrubs,  and  Herbs.  —  Plants 
of  the  largest  size  with  a  main  trunk  of  a 
woody  structure   are   called  trees.     Shrubs 
differ  from  trees  in  their  smaller  size,  and 

generally  in  having  several  stems  which  proceed  from  the 
ground  or  near  it  or  in  having  much^forked  stems.  The 
witch-hazel,  the  dogwoods,  and  the  alders,  for  instance, 
are  most  of  them  classed  as  shrubs  for  this  reason,  though 
in  height  some  of  them  equal  the  smaller  trees.  Some  of 


FIG.  34.  —  Leaf-Bearing  Spine 
of  Honey  Locust. 


70 


FOUNDATIONS   OF   BOTANY 


the  smallest  shrubby  plants,  like  the  dwarf  blueberry,  the 
wintergreen,  and  the  trailing  arbutus,  are  only  a  few  inches 


FlG.  35.  —  Tip  of  a  Branch  of  Magnolia,  illustrating  Forking  due  to 
Terminal  Flower-Buds. 

A,  oldest  flower-bud  scar  ;   B,  C,  D,  scars  of  successive  seasons  after  A;  L,  leaf- 
buds  ;  F,  flower-buds. 

in  height,  but  are  ranked  as  shrubs  because  their  woody 
stems  do  not  die  quite  to  the  ground  in  winter. 

Herbs  are  plants  whose  stems  above  ground  die  every 
winter. 


STEMS 


71 


86,  Annual,  Biennial,  and  Perennial  Plants.  —  Annual 
plants  are  those  which  live  but  one  year,  biennials  those 
which  live  two  years 
or  nearly  so. 

Some  annual  plants 
may  be  made  to  live 
over  winter,  flower- 
ing in  their  second 
summer.  This  is  true 
of  winter  wheat  and 
rye  among  cultivated 
plants. 

Perennial  plants  live  for  a  series  of 
years.  Many  kinds  of  trees  last  for 
centuries.  The  Galifornian  giant  redwoods,  or  Sequoias 
(Fig.  32),  which  reach  a  height  of  over  300  feet  under 
favorable  circumstances,  live  nearly  2000  years ;  and  some 


s 


FIG.  30.  — A  Portion  of 

the  Branch  of  Fig.  35. 

(Natural  size.) 


FIG.  37.  —Twigs  and 

Branches  of  the 

Birch. 


monstrous  cypress  trees  found  in  Mexico  were  thought  by 
Professor  Asa  Gray  to  be  from  4000  to  5000  years  old. 


72 


FOUNDATIONS   OF   BOTANY 


87.  Stemless  Plants.  —  As  will  be  shown  later  (Chap- 
ter XXX),  plants  live  subject  to  a  very  fierce  competition 
among  themselves  and  exposed  to  almost  constant  attacks 
from  animals. 

While  plants  with  long  stems  find  it  to  their  advantage 
to  reach  up  as  far  as  possible  into  the  sunlight,  the  cinque- 
foil,  the  white  clover, 
the  dandelion,  some 
spurges,  the  knot- 
grass, and  hundreds 
of  other  kinds  of 
plants  have  found 
safety  in  hugging 
the  ground. 

Any  plant  which 
can  grow  in  safety 
under  the  very  feet 
of  grazing  animals 
will  be  especially 
likely  to  make  its 
way  in  the  world, 
since  there  are  many 
places  where  it  can 
flourish  while  ordi- 
nary plants  would  be  destroyed.  The  bitter,  stemless 
dandelion,  which  is  almost  uneatable  for  most  animals, 
unless  cooked,  which  lies  too  near  the  earth  to  be  fed 
upon  by  grazing  animals,  and  which  bears  being  trodden 
on  with  impunity,  is  a  type  of  a  large  class  of  hardy  weeds. 
The  so-called  stemless  plants,  like  the  dandelion  (Fig.  38), 
and  some  violets,  are  not  really  stemless  at  all,  but  send 


FIG.  38.  —The  Dandelion  ; 
Stemless  Plant. 


a  so-called 


STEMS 


73 


out  their  leaves  and  flowers  from  a  very  short  stem,  which 
hardly  rises  above  the  surface  of  the  ground. 

88.  Climbing  and  Twining  Stems.1  —  Since  it  is  essen- 
tial to  the  health  and  rapid  growth  of  most  plants  that 
they  should  have  free  access 
to  the  sun  and  air,  it  is  riot 
strange  that  many  should 
resort  to  special  devices  for 
lifting  themselves  above 
their  neighbors.  In.  tropi- 
cal forests,  where  the  dark- 
ness of  the  shade  anywhere 
beneath  the  tree-tops  is  so 
great  that  few  flowering 
plants  can  thrive  in  it,  the 
climbing  plants  or  lianas 
often  run  like  great  cables 
for  hundreds  of  feet  before 
they  can  emerge  into  the  sun- 
shine above.  In  temperate 
climates  no  such  remarkable 
climbers  are  found,  but  many 
plants  raise  themselves  for 
considerable  distances.  The 
principal  means  to  which  they  resort  for  this  purpose  are  : 

(1)  Producing    roots    at   many   points  along  the  stem 
above  ground  and  climbing  on  suitable  objects  by  means 
of  these,  as  in  the  English  ivy  (Fig.  15). 

(2)  Laying  hold  of    objects  by   means   of    tendrils   or 
twining  branches  or  leaf-stalks,  as  shown  in  Figs.  40,  41. 

1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  p.  669. 


FIG.  39.  —  Lianas  strangling  a  Palm. 


T4 


FOUNDATIONS   OF   BOTANY 


room. 


•/*/ 


(3)  Twining  about  any  slender  upright  support,  as 
shown  in  Fig.  42. 

89,  Tendril-Climbers.  —  The  plants  which  climb  by 
means  of  tendrils  are  important  subjects  for  study,  but 
they  cannot  usually  be  managed  very  well  in  the  school- 
Continued  observation  soon  shows  that  the  tips  of 
tendrils  sweep  slowly  about  in 
the  air  until  they  come  in  contact 
with  some  object  about  which 
they  can  coil  themselves.  After 
the  tendril  has  taken  a  few  turns 
about  its  support,  the  free  part  of 
the  tendril  coils  into  a  spiral  and 
thus  draws  the  whole  stem  toward 
the  point  of  attachment,  as  shown 
in  Fig.  40.  Some  tendrils  are 
modified  leaves  or  stipules,  as 
shown  in  Fig.  104  ;  others  are 
modified  stems. 

90.  Twiners.  —  Only  a  few  of 
the  upper  internodes  of  the  stem 
of  a  twiner  are  concerned  in  pro- 
ducing the  movements  of  the  tip 
of  the  stem.  This  is  kept  revolving  in  an  elliptical  or 
circular  path  until  it  encounters  some  roughish  and  not  too 
stout  object,  about  which  it  then  proceeds  to  coil  itself. 

The  movements  of  the  younger  internodes  of  the  stems 
of  twiners  are  among  the  most  extensive  of  all  the  move- 
ments made  by  plants.  A  hop-vine  which  has  climbed  to 
the  top  of  its  stake  may  sweep  its  tip  continually  around 
the  circumference  of  a  circle  two  feet  in  diameter,  and  the 


FIG  40.  — Coiling  of  a  Tendril 
of  Bryony. 


STEMS 


75 


common  wax-plant  of  the  greenhouses  sometimes  describes 
a  five-foot  circle,  the  tip  moving  at  the  rate  of  thirty-two 
inches  per  hour.1  This  circular  motion  results  from 
some  cause  not  yet  fully  understood  by  botanists.2 

The  direction  in  which  twiners  coil  about  a  supporting 
object  is  almost  always  the  same  for  each  species  of  plant, 
but  not  the  same  for  all 
species.  Tn  the  hop  it  is  as 


FIG.  41.  —  Coiling  of  Petiole  of  Dwarf 
Tropseolurn. 


FIG.  42.  — Twining  Stem  of  Hop. 


shown  in  Fig.  42.  Is  it  the  same  as  in  the  bean?  in  the 
morning-glory  ? 

91.  Underground  Stems.  —  Stems  which  lie  mainly  or 
wholly  underground  are  of  frequent  occurrence  and  of 
many  kinds. 

In  the  simplest  form  of  rootstock  (Fig.  43),  such  as  is 

1  See  article  on  Climbing  Plants,  by  Dr.  W.  J.  Beal,  in  the  American 
Naturalist,  Vol.  IV,  pp.  405-415. 

2  See  Strasburger,  Noll,  Schenk,  and  Schimper,  Text-Book,  pp.  258-262; 
also  Vines,  Students'  Text-Book  of  Botany,  London  and  New  York,  1894, 
pp.  759,  760. 


76  - 


FOUNDATIONS   OF   BOTANY 


found  in  some  mints  and  in  many  grasses  and  sedges,  the 
real  nature  of  the  creeping  underground  stem  is  shown  by 

the  presence  upon  its  sur- 
face of  many  scales,  which 
are  reduced  leaves.  Root- 
stocks  of  this  sort  often 
extend  horizontally  for 
long  distances  in  the  case 
of  grasses  like  the  sea  rye 
grass  (Plate  I),  which  roots 
itself  firmly  and  thrives  in 
shifting  sand-dunes.  In 
the  stouter  rootstocks,  like 
that  of  the  iris  (Fig.  44) 
and  the  Caladium  (Fig. 
45),  this  stem-like  charac- 
ter is  less  evident.  The 
potato  is  an  excellent  ex- 
ample of  the  short  and 
much-thickened  under- 
ground stem  known  as  a 
tuber. 

It  may  be  seen  from  Fig. 
46   that  the   potatoes   are 
none  of  them  borne  on  true 
roots,  but  only  on  subter- 
raiiean 
branches, 
which  are 

FlG.  43.— Rootstock  of  Cotton-Grass  (Krio/tJiorum).  S  to  U  t  6  T 

and  more  cylindrical  than  most  of  the  roots.     The  "  eyes  " 


STEMS 


77 


which  they  bear  are  rudi- 
mentary leaves  and  buds. 

Bulbs,  whether  coated 
like  those  of  the  onion  or 
the  hyacinth  (Fig.  47),  or 
scaly  like  those  of  the 
lily,  are  merely  very  short 
and  stout  underground 
stems,  covered  with  closely 
crowded  scales  or  layers 
which  represent  leaves  or 
the  bases  of  leaves  (Fig.  48). 

The  variously  modified 
forms  of  underground 
stems  just  discussed,  illus- 


FIG.  44. —  Roots,  Rootstocks,  and 
Leaves  of  Iris. 

trate  in  a  marked  way  the  storage 
of  nourishment  during  the  winter 
(or  the  rainless  season,  as  the  case 
may  be)  to  secure  rapid  growth  dur- 
ing the  active  season.  It  is  inter- 
esting to  notice  that  nearly  all  of 
the  early-flowering  herbs  in  temper-  *•  fcermiHnal  bu<* ;  b>>  bud*  ar- 

•*  ranged  in  circles  where  bases 

ate    Climates,    like    the    CrOCUS,    the         of  leaves  were  attached ;  «, 

snowdrop,    the    spring-beauty,    the  ' 


FIG.  45.  —  Rootstock  of  Cala- 
diura  (Colocasia). 


78 


FOUNDATIONS   OF   BOTANY 


tulip,  and  the  skunk-cabbage,  owe  their  early-blooming 
habit  to  richly  stored  underground  stems  of  some  kind, 
or  to  thick,  fleshy  roots. 

92.  Condensed  Stems.  —  The  plants  of  desert  regions 
require,  above  all,  protection  from  the  extreme  dryness  of 
the  surrounding  air,  and,  usually,  from  the  excessive  heat 

of  the  sun.  Ac- 
cordingly, many 
desert  plants  are 
found  quite  desti- 
tute of  ordinary 
foliage,  exposing 
to  the  air  only  a 
small  surface.  In 
the  melon-cactuses 
(Fig.  49)  the  stem 
appears  reduced 
to  the  shape  in 
which  the  least 
possible  surface  is 
FiG.46.-parto(aPota,oPiant.  presented  by  a 

The  dark  tuber  in  the  middle  is  the  one  from  which         plant    of    given 
the  plant  has  grown. 


a  globular  form.  Other  cactuses  are  more  or  less  cylindri- 
cal or  prismatic,  while  still  others  consist  of  flattened 
joints  ;  but  all  agree  in  offering  much  less  area  to  the  sun 
and  air  than  is  exposed  by  an  ordinary  leafy  plant. 

93.  Leaf  -Like  Stems.  —  The  flattened  stems  of  some  kinds 
of  cactus  (especially  the  common,  showy  Phyllocactus)  are 
sufficiently  like  fleshy  leaves,  with  their  dark  green  color 
and  imitation  of  a  midrib,  to  pass  for  leaves.  There  are, 


STEMS 


79 


.  47.  —Bulb  of  Hyacinth. 
(Exterior  view  and  split  lengthwise.) 


however,  a  good  many  cases  in  which  the  stem  takes  on 

a  more  strikingly  leaf-like  form.     The  common  asparagus 

sends  up  in  spring  shoots 
that  bear  large  scales  which 
are  really  reduced  leaves. 
Later  in  the  season,  what 
seem  like  thread-like  leaves 
cover  the  much-branched 
mature  plant,  but  these 
green  threads  ^ 

are  actually  mi- 
nute branches,         \MI\bl 
which  perform 
the     work     of 

leaves   (Fig.   50).     The   familiar    greenhouse 

climber,   wrongly  known  as  smilax  (properly 

called    Myrsiphyllum),    bears    a   profusion    of 

what    appear    to    be    delicate    green    leaves 

(Fig.  51).     Close  study,  however,  shows  that 

these  are  really  short,  flattened  branches, 

and  that  each  little  branch  springs  from 

the  axil  of  a  true   leaf,   ?,   in   the  form 

of  a  minute  scale.     Sometimes  a  flower 

and  a  leaf-like   branch  spring  from   the 

axil  of  the  same  scale. 

Branches  which,  like  those   of   Myrsi- 

phyllum,  so  closely  resemble  leaves  as  to 

be  almost  indistinguishable  from  them  are 

called  cladopJiylls. 

94.    Modifiability  of  the  Stem. — The  stem  may,  as  in  the 

tallest  trees,  in  the  great  lianas  of  South  American  forests, 


sea 


FIG.  48.  —  Longitu- 
dinal Section  of 
an  Onion  Leaf. 

sea,  thickened  base 
of  leaf,  forming  a 
bulb-scale;  s.thin 
sheath  of  leaf ;  bl, 
blade  of  the  leaf  ; 
int,  hollow  inte- 
rior of  blade. 


80 


FOUNDATIONS   OF  BOTANY 


FIG.  50.  — A  Spray  of  a  Common  Asparagus  (not  the  edible  species). 


STEMS 


81 


or  the  rattan  of  Indian  jungles,  reach  a  length  of  many 
hundred  feet.  On  the  other  hand,  in  such  "sternless" 
plants  as  the  primrose  and  the  dandelion,  the  stem  may  be 
reduced  to  a  fraction  of  an  inch  in  length.  It  may  take 


FIG.  51.  — Stem  of  "  Smilax  "  (Myrsiphyllum). 

I,  scale-like  leaves  ;  <7,  cladophyll,  or  leaf-like  branch,  growing  in  the  axil  of  the 
leaf  ;  jx'd,  flcwr-stalk,  growing  in  the  axil  of  a  leaf. 

on  apparently  root-like  forms,  as  in  many  grasses  and 
sedges,  or  become  thickened  by  underground  deposits  of 
starch  and  other  plant-food,  as  in  the  iris,  the  potato,  and 
the  crocus.  Condensed  forms  of  stem  may  exist  above 
ground,  or,  on  the  other  hand,  branches  may  be  flat  and 


82  FOUNDATIONS   OF   BOTANY 

thin  enough  closely  to  imitate  leaves.  In  short,  the  stem 
manifests  great  readiness  in  adapting  itself  to  the  most 
varied  conditions  of  existence. 


95.    Review  Summary  of  Stems.1 
Kinds  of  branching  due  to  leaf  arrangement      .... 


Condensed  stems  above  ground 


Leaf -like  stems 


{i 


Kinds  of  tree-trunk  due  to  greater  or  less  predominance       f  1 
of  terminal  bud 1  2. 

f1- 

Classes  of  plants  based  on  amount  of  woody  stem      .     .     -j  2. 

U. 

f1- 

Classes  of  plants  based  on  duration  of  life -j  2. 

U 

f1- 

Various  modes  of  climbing V  2. 

U 

F1- 

Kinds  of  underground  stem •<  2. 

1 3. 


1  Where  it  is  possible  to  do  so,  make  sketches ;  where  this  is  not  possible, 
give  examples  of  plants  to  illustrate  the  various  kinds  or  classes  of  plants  in 
the  summary. 


CHAPTER    VI 


STRUCTURE    OF   THE    STEM 


STEM   OF   MONOCOTYLEDONOUS   PLANTS 

96,  Gross  Structure.  —  Refer  back  to  the  sketches  of  the  corn- 
seedling,  to  recall  something  of  the  early  history  of  the  corn-stem. 
Study  the  external  appearance  of  a  piece  of  corn-stem  or  bamboo 
two  feet  or  more  in  length.  Note  the  character  of  the  outer  surface. 
Sketch  the  whole  piece  and  label  the  enlarged  nodes  and  the  nearly 
cylindrical  internodes.  Cut  across  a  corn-stem  and  examine  the  cut  sur- 
face with  the  magnifying  glass. 
Make  some  sections  as  thin  as 
they  can  be  cut  and  examine 
with  the  magnifying  glass 
(holding  them  up  to  the  light) 
or  with  a  dissecting  microscope. 
Note  the  firm  rind,  composed 
of  the  epidermis  and  underlying 
tissue,  the  large  mass  of  pith 
composing  the  main  bulk  of  the 
stem,  and  the  many  little  harder 
and  more  opaque  spots,  which 
are  the  cut-off  ends  of  the 
woody  threads  known  asj£6ro- 
vascular  bundles  (Fig.  52). 

Split  a  portion  of  the  stern 
lengthwise  into  thin  translucent    ci>,  fibro-vascular  bundles  ;  gc,  pithy  material 
slices  and  notice  whether  the 

bundles  seem  to  run  straight  up  and  down  its  length ;  sketch  the 
entire  section  x  2.  Every  fibro-vascular  bundle  of  the  stem  passes  out- 
ward through  some  node  in  order  to  connect  with  some  fibro-vascular 

83 


FIG.  52.  —Diagrammatic  Cross-Section 
of  Stem  of  Indian  Corn. 


84 


FOUNDATIONS   OF   BOTANY 


bundle  of  a  leaf.  This  fact  being  known  to  the  student  would  lead 
him  to  expect  to  find  the  bundles  bending  out  of  a  vertical  position 
more  at  the  nodes  than  elsewhere.  Can  this  be  seen  in  the  stem 
examined  ? 

Observe  the  enlargement  and  thickening  at  the  nodes,  and  split 
one  of  these  lengthwise  to  show  the  tissue  within  it. 

Compare  with  the  corn-stem  a  piece  of  palmetto  and  a  piece  of 
cat-brier  (Smilax  rotundifolia,  S.  hispiila,  etc.),  and  notice  the  simi- 
larity of  structure,  except  for  the  fact  that  the  tissue  in  the  palmetto 
and  the  cat-brier  which  answers  to  the  pith  of  the  corn-stem  is  much 
darker  colored  and  harder  than  corn-stem  pith.  Compare  also  a  piece 
of  rattan  and  of  bamboo. 

97.  Minute  Structure.  —  Cut  a  thin  cross-section  of  the  corn-stem, 
examine  with  a  low  power  of  the  microscope,  and  note : 

(a)  The  rind  (not  true  bark),  composed  largely  of  hard,  thick- 
walled  dead  cells,  known  as  sclerenchyma  fibers. 

(&)  The  fibre-vascular  bundles.  Where  are  they  most  abundant  V 
least  abundant  ? 

(c)  The  pith,  occupying  the  intervals  between  the  fibro-vascular 
bundles. 

Study  the  bundles  in  various  portions  of  the  section  and  notice 
particularly  whether  some  are  more  porous  than  others.     Explain. 
Sketch  some  of  the  outer  and  some  of  the 
inner  ones. 

A  more  complicated  kind  of  monocoty- 
ledonous  stem-structure  can  be  studied  to 
advantage  in  the  surgeons'  splints  cut  from 
yucca-stems  and  sold  by  dealers  in  surgical 
supplies. 

.  53.  -Diagrammatic         98'    Mechanical     Function    of    the 
cross-section  of  stem  of    Manner  of    Distribution  of  Material 

Bulrush   (Scirpus),  a       .         ,,  .     ,     ,  _,,  r™ 

Hollow  cylinder  with     in    Monocotyledonous    Stems.  -     ihe 

strengthening  Fibers.       weU-known  strength  and  lightness  of 

the  straw  of  our  smaller  grains  and  of  rods  of  cane  or 

bamboo  are  due  to  their  form.     It  can  readily  be  shown 


STRUCTURE   OF   THE   STEM 


85 


by  experiment  that  an  iron  or  steel  tube  of  moderate  thick- 
ness, like  a  piece  of  gas-pipe,  or  of  bicycle-tubing,  is  much 
stiffer  than  a  solid  rod  of  the  same  weight  per  foot.  The 
oat  straw,  the  stems  of  bulrushes  (Fig.  53),  the  cane  (of 
our  southern  canebrakes),  and  the  bamboo  are  hollow 
cylinders  ;  the 
cornstalk  is  a 
solid  cylinder, 
but  filled  with  a 
very  light  pith. 
The  flinty  outer 
layer  of  the 
stalk,  together 
with  the  closely 
packed  scleren- 
chyma  fibers  of 
the  outer  rind 
and  the  frequent 
fibro-vascular 
bundles  just 
within  this,  are 
arranged  in  the 
best  way  to  se- 
cure stiffness. 
In  a  general 
way,  then,  we  may  say  that  the  pith,  the  bundles,  and  the 
sclerenchymatous  rind  are  what  they  are  and  where  they 
are  to  serve  important  mechanical  purposes.  But  they 
have  other  uses  fully  as  important  (Fig.  78). 

99.    Growth  of  Monocotyledonous  Stems  in  Thickness.  — 
In    most    woody    monocotyledonous  stems,   for  a  reason 


FIG.  54.  —  Group  of  Date-Palms. 


86  FOUNDATIONS   OF   BOTANY 

which,  will  be  explained  later  in  this  chapter,  the  increase 
in  thickness  is  strictly  limited.  Such  stems,  therefore,  as 
in  many  palms  (Fig.  54)  and  in  rattans,  are  less  conical 
and  more  cylindrical  than  the  trunks  of  ordinary  trees 
and  are  also  more  slender  in  proportion  to  their  height. 


STEM   OF   DICOTYLEDONOUS   PLANTS 

100.  Gross  Structure  of  an  Annual  Dicotyledonous  Stem.  —  Study 
the  external  appearance  of  a  piece  of  sunflower-stem  several  inches 
long.     If  it  shows  distinct  nodes,  sketch  it.     Examine  the  cross- 
section  and  sketch  it  as  seen  with  the  magnifying  glass  or  the  dissect- 
ing microscope.    After  your  sketch  is  finished,  compare  it  with  Fig.  55, 
which  probably  shows  more  details  than  your  drawing,  and  label 
the  parts  shown  as  they  are  labeled  in  that  figure.     Split  a  short 
piece  of  the  stem  lengthwise  through  the  center  and  study  the  split 
surface  with  the  magnifying  glass.      Take  a  sharp  knife  or  a  scalpel 
and  carefully  slice  and  then  scrape  away  the  bark  until  you  come  to 
the  outer  surface  of  a  bundle. 

Examine  a  vegetable  sponge  (Luffa),  sold  by  druggists,  and  notice 
that  it  is  simply  a  network  of  fibro-vascular  bundles.  It  is  the  skele- 
ton of  a  tropical  seed-vessel  or  fruit,  very  much  like  that  of  the  wild 
cucumber,  common  in  the  Central  States,  but  a  great  deal  larger. 

The  different  layers  of  the  bark  cannot  all  be  well  recognized  in  the 
examination  of  a  single  kind  of  stem.  Examine  (a)  the  cork  which 
constitutes  the  outer  layers  of  the  bark  of  cherry  or  birch  branches 
two  or  more  years  old.  Sketch  the  roundish  or  oval  spongy  lenticels 
on  the  outer  surface  of  the  bark.  How  far  in  do  they  extend  ?  Exam- 
ine (&)  the  green  layer  of  bark  as  shown  in  twigs  or  branches  of 
Forsythia,  cherry,  alder,  box-elder,  wahoo,  or  willow.  Examine  (c) 
the  white,  fibrous  inner  layer,  known  as  hard  bast,  of  the  bark  of 
elm,  leatherwood,  pawpaw,  or  basswood. 

101.  Minute  Structure  of  the  Dicotyledonous  Stem.  —  Study,  first 
with  a  low  and  then  with  a  medium  power  of  the  compound  micro- 
scope, thin  cross-sections  of  clematis-stem  cut  just  before  the  end  of 


STRUCTURE    Olf   THE   STEM  51 

the  first  season's  growth.1  Sketch  the  whole  section  without  much 
detail,  and  then  make  a  detailed  drawing  of  a  sector  running  from 
center  to  circumference  and  just  wide  enough  to  include  one  of  the 
large  bundles.  Label  these  drawings  in  general  like  Figs.  55,  56. 


FIG.  55.  —  Diagrammatic  Cross-Section  of  an  Annual  Dicotyledonous  Stem. 
(Somewhat  magnified.) 

p,  pith  ;  /r,  woody  or  fibro-vascular  bundles  ;  e,  epidermis  ;   6,  bundles  of  hard 
bast  fibers  of  the  bark. 


FIG.  56.  —Diagrammatic  Cross-Section  of  One- Year-Old  Aristolochia  Stem. 
(Considerably  magnified.) 

e,  region  of  epidermis ;  6,  hard  bast ;  o,  outer  or  bark  part  of  a  bundle  (the 
cellular  portion  under  the  letter)  ;  w,  inner  or  woody  part  of  bundle  ;  c,  cam- 
bium layer  ;  p,  region  of  pith  ;  TO,  a  medullary  ray. 

The  space  between  the  hard  bast  and  the  bundles  is  occupied  by  thin-walled, 
somewhat  cubical  cells  of  the  bark. 


1  Clematis  virginiana  is  simpler  in  structure  than  some  of  the  other  woody 
species.     Aristolochia  sections  will  do  very  well. 


88  FOUNDATIONS   OF   BOTANY 

Note: 

(a)  The  general  outline  of  the  section. 

(ft)  The  number  and  arrangement  of   the  bundles.      (How 
many  kinds  of  bundles  are  there?) 

(c)  The  comparative  areas  occupied  by  the  woody  part  of  the 

bundle  and  by  the  part  which  belongs  to  the  bark. 

(d)  The  way  in  which  the  pith  and  the  outer  bark  are  con- 

nected (and  the  bundles  separated)  by  the  medullary  rays. 


FIG.  57.  —  One  Bundle  from  the  Preceding  Figure.    ( x  100.) 

w,  wood-cells  ;  d,  ducts.    The  other  letters  are  as  in  Fig.  56.    Many  sieve-cells 
occur  in  the  region  just  outside  of  the  cambium  of  the  hundle. 

Examine  a  longitudinal  section  of  the  same  kind  of  stem,  to  find 
out  more  accurately  of  what  kinds  of  cells  the  pith,  the  bundles,  and 
the  outer  bark  are  built.  Which  portion  has  cells  that  are  nearly 
equal  in  shape,  as  seen  in  both  sections  ? 


STRUCTURE   OF   T 


STKM 


89 


102.  Mechanical  Importance  of  Distribution  of  Material 
in  the  Dicotyledonous  Stem.  — It  is  easy  to  see  that  those 
tissues  which  are  tough,  like  hard  bast,  and  those  which 
are  both  tough  and  stiff,  like  wood  fibers,  are  arranged  in 
a  tubular  fashion  in  young  dicotyledonous  stems  as  they 
are  in  some  monocotyledonous  ones  (Fig.  53).  Sometimes 
the  interior  of  the  stem  is  quite  hollow,  as,  for  example, 


ck         b          s         c     w    d    m 


FIG.  58.  —  Stem  of  Box-Elder  One  Year  Old.    (Much  magnified.) 
A,  lengthwise  (radial)  section  ;  B,  cross-section  ;  e,  epidermis  ;  ck,  cork  ;  6,  hard 
bast ;    s,  sieve-cells  ;    c,  cambium  ;    w,  wood-cells  ;   m,  medullary  rays  ;    d, 
ducts  ;  p,  pith. 

in  the  stems  of  balsams,  melons,  cucumbers,  and  squashes, 
and  in  the  flower-stalks  of  the  dandelion.  In  older  stems, 
such  as  the  trunks  of  trees,  the  wood  forms  a  pretty  nearly 
solid  cylinder. 

Stiffness  in  dicotyledonous  stems  is  secured  mainly  in 
two  ways  :  (1)  by  hard  bast  fibers,  (2)  by  wood  fibers. 
Which  of  these  types  does  the  stem  (Fig.  55)  represent? 
Which  does  the  flax-stem  (Fig.  60)  represent? 


90  FOUNDATIONS   OF  BOTANY 

Notice  that  in  both  types  bast  fibers  and  wood  fibers  are 
present,  but  the  proportions  in  (1)  and  (2)  vary  greatly. 

103,  Kinds  of  Cells  which  compose  Stems.  —  The  stu- 
dent has  already  seen  something  of  cells  in  the  seed,  in 
the  roots  of  seedlings  and  mature  plants,  and  in  several 
kinds  of  stems.  But  he  will  need  to  become  acquainted 
with  a  much  larger  variety  of  cells  in  the  stem.  The  fol- 
lowing materials  will  serve  to  illustrate  some  of  the  most 
important  forms.1 

Examine  with  a  half-inch  objective  and  one-inch  eyepiece  (or 
higher  power)  these  preparations  (1-9  below)  : 

Study  very  carefully  each  of  the  sections  described,  find  in  it 
the  kind  of  cell  referred  to  in  the  corresponding  number  (1—9)  of 
the  following  section  (104),  and  make  a  good  sketch  of  a  group  of 
cells  of  each  kind  as  actually  seen  under  the  microscope.2 

(1)  Very  thin  sections  of  the  epidermis  of  a  potato,  some  cut  parallel 
to  the  surface  (tangential),  others  cut  at  right  angles  to  the  epidermis. 

(2)  Thin  sections  of  the  green  layer  of  the  bark  of  Forsythia, 
spindle  tree  (Euonymus),  or  box-elder  (Neyundo). 

(3)  Thin  cross-sections  and  longitudinal  sections  of  the  inner  bark 
of  linden  twigs,  or  of  full-grown  stems  of  flax. 

(4)  Longitudinal  sections  of  the  stem  of  squash  or  cucumber  plants. 

(5)  Thin  cross-sections  of  young  twigs  of  pine  or  oak,  cut  in  late 
summer. 

(6)  Thin  cross-sections  and  longitudinal  sections,  cut  from  pith 
toward  bark  (radial}  of  young  wood  of  sycamore,  of  sassafras,  or  of 
box -elder. 

(7)  Thin  longitudinal  sections  of  the   stem  of  castor-oil  plant 
(Ricinus)    or  of  the   stalk    (peduncle)   on  which  the  fruit  of    the 
banana  is  supported. 

1  These  studies  may  be  made  from  sections  cut  by  the  pupil,  by  the  teacher,  or 
by  a  professional  hand,  as  circumstances  may  dictate.   The  soft  bast  (No.  4,  see 
p.  91)  can  best  be  studied  in  good  prepared  sections  obtained  of  the  dealers. 

2  Nothing  can  do  so  much  to  make  these  studies  valuable  as  for  the  teacher 
to  correct  in  class  the  errors  of  most  frequent  occurrence  in  the  drawings,  by 
aid  of  his  own  camera  lucida  drawings  of  the  same  objects. 


STRUCTURE    OF   THE    STEM 


(8)  Thin  longitudinal  radial  sections  of  sycamore,  of  sassafras, 
maple,  or  box-elder  wood. 

(9)  Thin  sections  of  elder  pith,  sunflower-stem  pith,  or  of  so-called 
Japanese  "  rice-paper." 

104.    Names  of  the  Cells  of  Bark,  Wood,  and  Pith.  — No 
two  varieties  of  stems  will  be  found  to  consist  of  just  the 


B 


FIG.  59.  —  A,  B,  C, 
D,  Isolated  Wood- 
Cells  and  Bast- 
Cells  of  Linden. 

A,B,  wood  fibers;  C, 
piece  of  a  vessel ; 
D,  bast  fiber;  E,SL 
partitioned,  woody 
fiber  from  Euro- 
pean ivy.  (Much 
magnified.) 


FIG.  60.  —  Part  of  Cross-Section  of  Stem  of  Flax. 
(Much  magnified.) 

e,  epidermis  ;   b,  hard  bast ;  s,  sieve-cells  ;  w,  wood. 

same  kinds  of  cells,  present  in  the  same 
proportions,  but  it  is  easy  to  refer  to  illus- 
trations which  will  serve  to  identify  the 
kinds  of  cells  found  in  the  studies  of  the 
preceding  section.  They  are  : 


(1) 
(2) 


flax, 


Cork-cells    of    the    epidermis    (e.g., 

Fig.  60,  e}. 
Cells  of  the  green  bark  (e.g.,  flax,  Fig.  60), 

between  b  and  e. 
(3)    Hard  bast  (Fig.  60). 
(4)  Soft  bast  (e.g.,  flax,  Fig.  60,  s,  for  the  cross-section  and  (very 
greatly  magnified)  Figs.  63,  64,  for  the  lengthwise  section).1 

i  The  sieve-tubes  shown  in  these  figures  are  only  one  of  several  kinds  of 
cell  found  in  soft  bast,  but  they  are  the  most  peculiar  and  characteristic  ones. 
(See  Strasburger,  Noll,  Schenk,  and  Schimper's  Text-Book,  pp.  102-104.) 


92 


FOUNDATIONS   OF   BOTANY 


(5)  Cambium  (e.g.,  Fig.  57,  c). 

(6)  Wood-cells  (e.g.,  Figs.  58,  72-73). 

(7)  Vessels  or  ducts  (e.g.,  Figs.  58  and  62). 

(8)  Wood  parenchyma  (e.g.,  Figs.  58  and  72  in  the  medullary 

rays). 

(9)  Pith  (e.g.,  Figs.  55,  57). 

105.    Structure  of  Coniferous  Wood In  the   wood   of 

the  cone-bearing  trees  of  the  pine  family  regular  ducts  or 


FIG.  61.  FIG.  62. 

FIG.  61.  —  A  Group  of  Hard  Bast  Fibers.     (Greatly  magnified.) 
a,  cut-off  ends  ;  b,  lengthwise  section  of  fibers. 

FIG.  62.  —  A  Lengthwise  Section  (greatly  magnified)  of  a  Group  of  Spiral  Vessels 
from  the  Stem  of  Sunflower.  At  the  top  of  the  figure  some  of  the  spiral 
threads  which  line  the  vessels  are  seen  partly  uncoiled. 

vessels  are  lacking.     The  main  bulk  of  the  wood  is  com- 
posed of  long  cells  (often  called  tracheids),  marked  with 


STRUCTURE    OF   THE   STEM 


peculiar  pits.  These  pits,  when  young,  are  shaped  much 
like  two  perforated  watch-glasses,  placed  against  a  piece 
of  cardboard,  with  their  concave  sides  toward  each  other 


FTG.  G3.  FIG.  64.  FIG.  65. 

FIG.  63.  —  Part  of  a  Sieve-Tube  from  Linden. 
s,  sieve-plates  on  the  cell-wall,    (x  about  900.) 

FIG.  64.  — Parts  of  Sieve-Tubes  as  found  in  Plants  of  the  Gourd  Family. 
(Greatly  magnified.) 

s,  s,  a  sieve-plate  seen  edgewise  ;  above  it  a  similar  one,  surface  view. 

FIG.  65.  —Cross-Section  of  Fir  Wood. 
s,  a  resin  passage  ;  m,  medullary  rays.     (Much  magnified.) 


94 


FOUNDATIONS   OF   BOTANY 


(see  Fig.  66,  t").  The  cardboard  represents  a  part  of  the 
cell- wall  common  to  two  adjacent  cells,  and  the  watch- 
glasses  are  like  the  convex  border  bulging  into  each  cell. 

When  the  cells  grow  old  the 
partition  in  each  pit  very  com- 
monly breaks  away  and  leaves 
a  hole  in  the  cell-wall. 

106.  Tissues.  —  A  mass  of 
similar  cooperating  cells  is  called 
a  tissue.1  Two  of  the  principal 
classes  which  occur  in  the  stem 
are  parencliymatous  tissue  and 
prosenchymatous  tissue.  Paren- 

€\  ^^  J6N  ^  ")       cliyma  is  well  illustrated  by  the 

V\r\  green  layer  of  the  bark,  by  wood 

parenchyma,  and  by  pith.  Its 
cells  are  usually  somewhat 
roundish  or  cubical,  at  any  rate 
not  many  times  longer  than  wide, 
and  at  first  pretty  full  of  proto- 
plasm. Their  walls  are  not 
generally  very  thick.2  Prosen- 
chyma,  illustrated  by  hard  bast 
and  masses  of  wood-cells,  con- 
sists of  thick-walled  cells  many 

times  longer  than  wide,  containing  little  protoplasm  and 

often  having  little  or  no  cell-cavity. 

As  a  rule  the  stems  of  the  most  highly  developed  plants 

owe  their  toughness  and  their  stiffness  mainly  to  prosen- 


FIG.  66.  —  Longitudinal  Radial  Sec- 
tion through  a  Rapidly  Growing 
Young  Branch  of  Pine. 

t,  t',  t",  bordered  pits  on  wood-cells  ; 
st,  large  pits  where  medullary 
rays  lie  a  g  a  i  n  s  t  w  o  o  d  -  c  e  1 1  s. 
(Much  magnified.) 


1  See  Vines'  Students'  Text-Book  of  Botany,  London,  1894,  pp.  131-144. 

2  Excepting  when  they  are  dead  and  emptied,  like  those  of  old  pith. 


STRUCTURE   OF  THE   STEM 


95 


FIG.  67o  —  Collenchymatous 
and  Other  Tissue  from  Stem    IOr  instance, 
of  Balsam  (Inpatiens).  ^  ^  gmw_ 

e,  epidermis ;  c,  collenchyma; 
i,  intercellular  spaces  be-     ing     point 
tween    large  parenchyma-     between  the 
cells. 

two  rudi- 
mentary leaves  of  a  bean-plumule, 
the  cells  are  all  of  thin-walled 
formative  tissue  and  look  a  good 
deal  alike.  This  condition  of 
things  is  quickly  succeeded  by 
one  in  which  there  is  a  cylinder 
(appearing  in  cross-sections  of  the 
stem  as  a  ring)  of  actively  growing 
tissue  x  (Fig.  68,  J.),  lying  between 
the  cortex  r  and  the  pith  m.  Soon 
the  cylinder  x  develops  into  a 
series  -  of  separate  nbro-vascular 
bundles  arranged  as  shown  in 
Fig.  68,  #,  and  these  again  in  a 
short  time  unite,  as  shown  at  C. 
A  comparison  of  this  last  portion 
of  the  figure  with  that  of  the 


chymatous  tissue.  In  some  (particu- 
larly in  fleshy)  stems  the  stiffness  is, 
however,  largely  due  to  collenchyma,  a 
kind  of  parenchyma  in  which  the  cells 
are  thickened  or  reinforced  at  their 
angles,  as  shown  in  Fig.  67. 

107.  Early  History  of  Stem-Struc- 
ture. —  In  the  very  young  parts  of 
stems,  such, 


B 


FIG.  68.  —  Transverse  Section 
through  the  Hypocotyl  of  the 
Castor-Oil  Plant  at  Various 
Stages. 

A,  after  the  root  has  just  ap- 
peared outside  the  testa  of  the 
seed";  B,  after  the  hypocotyl  is 
nearly  an  inch  long;  C,  at  the 
end  of  germination;  r,  cortex 
(undeveloped  bark);  m,  pith; 
st,  medullary  rays ;  fv,  nbro- 
vascular  bundles;  cb,  layer  of 
tissue  which  is  to  develop  into 
cambium.  (Considerably  mag- 
nified.) 


96  FOUNDATIONS   OF   BOTANY 

one-year-old  Aristolochia-stem  (Fig.  56)  shows  a  decided 
similarity  between  the  two.  In  both  cases  we  have  the 
central  pith,  the  regularly  grouped  bundles,  and  cambium 
(or  in  Fig.  68,  (7,  a  tissue  which  will  grow  into  cambium), 
-  part  of  it  in  the  bundles  and  part  of  it  between  them. 

In  the  young  monocotyledonous  stem  the  grouping  of 
the  bundles  is  less  regular  than  that  just  explained.  This 
is  shown  by  Fig.  52.  A  much  more  important  difference 
consists  in  the  fact  that  the  monocotyledonous  stem  has 
usually  no  permanent  living  cambium  ring.  Annual  dicoty- 
ledons, however,  are  also  destitute  of  permanent  cambium. 

108.  Secondary  Growth.  —  From  the  inside  of  the  cam- 
bium layer  the  wood-cells  and  duats  of  the  mature  stem 
are  produced,  while  from  its  outer  circumference  proceed 
the  new  layers  of  the  inner  bark,  composed  largely  of  sieve- 
cells  and  hard  bast.  From  this  mode  of  increase  the  stems 
of  dicotyledonous  plants  are  called  exogenous,  that  is,  out- 
side-growing. The  presence  of  the  cambium  layer  on  the 
outside  of  the  wood  in  early  spring  is  a  fact  well  known 
to  the  schoolboy,  who  pounds  the  cylinder  cut  from  an 
elder,  willow,  or  hickory  branch  until  the  bark  will  slip 
off  and  so  enable  him  to  make  a  whistle.  The  sweet  taste 
of  this  pulpy  layer,  as  found  in  the  white  pine,  the  slippery 
elm,  and  the  basswood,  is  a  familiar  evidence  of  the 
nourishment  which  the  cambium  layer  contains. 

With  the  increase  of  the  fibre-vascular  bundles  of  the 
wood  the  space  between  them,  which  appears  relatively 
large  in  Fig.  68,  becomes  less  and  less,  and  the  pith,  which 
at  first  extended  freely  out  toward  the  circumference  of 
the  stem,  is  at  length  only  represented  by  thin  plates,  the 
medullary  rays. 


STRUCTURE   OF   THE    STEM 


97 


These  are  of  use  in  storing  the  food  which  the  plant 
in  cold  and  temperate  climates  lays  up  in  the  summer  and 
fall  for  use  in  the  following  spring,  and  in  the  very  young 
stem  they  serve  as  an  important  channel  for  the  transfer- 
ence of  fluids  across  the  stem  from  bark  to  pith,  or  in  the 


FIG.  69.  —  Diagram  to  illustrate  Secondary  Growth  in  a  Dicotyledonous  Stem. 

7?,  the  first-formed  bark  ;  p,  mass  of  sieve-cells  ;  ifp,  mass  of  sieve-cells  between 
the  original  wedges  of  wood  ;  fc,  cambium  of  wedges  of  wood  ;  ic,  cambium 
between  wedges  ;  b,  groups  of  bast-cells  ;  fh,  wood  of  the  original  wedges  ; 
ifh,  wood  formed  between  wedges  ;  x,  earliest  wood  formed  ;  M,  pith. 

reverse  direction.  On  account,  perhaps,  of  their  impor- 
tance to  the  plants,  the  cells  of  the  medullary  rays  are 
among  the  longest  lived  of  all  plant-cells,  retaining 
their  vitality  in  the  beech  tree  sometimes,  it  is  said,  for 
more  than  a  hundred  years. 

After  the   interspaces  between  the   first  fibro-vascular 
bundles  have  become  filled  up  with  wood,  the  subsequent 


98  FOUNDATIONS   OF   BOTANY 

growth  must  take  place  in  the  manner  shown  in  Fig.  69. 
All  the  cambium,  both  that  of  the  original  wedges  of  wood, 
fc,  and  that,  ic,  formed  later  between  these  wedges,  con- 
tinues to  grow  from  its  inner  and  from  its  outer  face,  and 
thus  causes  a  permanent  increase  in  the  diameter  of  the  stem 
and  a  thickening  of  the  bark,  which,  however,  usually  at 
an  early  period  begins  to  peel  off  from  the  outside  and 
thus  soon  attains  a  pretty  constant  thickness.1  It  will  be 
noticed,  in  the  study  of  dicotyledonous  stems  more  than  a 
year  old,  that  there  are  no  longer  any  separate  nbro-vascular 
bundles.  The  process  just  described  has  covered  the  origi- 
nal ring  of  bundles  with  layer  after  layer  of  later  formed 
wood-cells,  and  the  wood  at  length  is  arranged  in  a  hollow 
cylinder. 

It  is  the  lack  of  any  such  ring  of  cambium  as  is  found 
in  dicotyledonous  plants,  or  even  of  permanent  cambium 
in  the  separate  bundles,  that  makes  it  impossible  for  the 
trunks  of  most  palm  trees  (Fig.  54)  to  grow  indefinitely 
in  thickness,  like  that  of  an  oak  or  an  elm.2 

109.  Grafting.  —  When  the  cambium  layer  of  any  vigor- 
ously growing  stem  is  brought  in  contact  with  this  layer 
in  another  stem  of  the  same  kind  or  a  closely  similar  kind 
of  plant,  the  two  may  grow  together  to  form  a  single  stem 
or  branch.  This  process  is  called  grafting,  and  is  much 
resorted  to  in  order  to  secure  apples,  pears,  etc.,  of  any 
desired  kind.  A  twig  from  a  tree  of  the  chosen  variety  is 
grafted  on  to  any  kind  of  tree  of  the  same  species  (or  some- 
times a  related  species),  and  the  resulting  stems  will  bear 
the  wished-for  kind  of  fruit.  Sometimes  grafting  comes 

1  See  Vines'  Students'  Text-Book  of  Botany,  London,  1894,  pp.  211,  212. 

2  See,  however,  Strasburger,   Noll,   Schenk   and    Schimper's   Text-Book, 
pp.  138,  139. 


STRUCTURE    OF   THE    STEM 


99" 


about  naturally  by  the  branches  of  a  tree  chafing  against  one 
another  until  the  bark  is  worn  away  and  the  cambium  layer 
of  each  is  in  contact  with  that  of  the  other,  or  two  separate 
trees  may  be  joined  by 
natural  grafting,  as  is 
shown  in  Fig.  70. 

110.  Stem-Structure 
of  Climbing  Shrubs.  - 
Some  of  the  most  remark- 
able kinds  of  dicotyle- 
donous stems  are  found 
in  climbing  shrubs.  The 
structure  of  many  of 
these  is  too  complicated 
to  be  discussed  in  a 
botany  for  beginners,  but 
one  point  in  regard  to 
them  is  of  much  inter- 
est. The  bundles  (as 
seen  in  the  clematis  and 
shown  in  Fig.  56)  are 
much  more  distinct  than 
in  most  other  woody 
stems.  Even  after  sev- 
eral years  of  growth  the 
wood  is  often  found  to  be 
arranged  in  a  number  of 
flattish  twisted  strands. 
It  is  evident  that  this  is  for  the  sake  of  leaving  the 
stem  flexible  for  twining  purposes,  just  as  a  wire  cable  is 
adapted  to  be  wound  about  posts  or  other  supports,  while 


FIG.  70.  —  Two  Ash  Trees  naturally 
grafted  together. 


100 


FOUNDATIONS   OF   BOTANY 


a  solid  steel  or  iron  rod  of  the  same  size  would  be  too 
stiff  for  this  use. 

111.  The  Dicotyledonous  Stem,  thickened  by  Secondary  Growth.— 
Cut  off,  as  smoothly  as  possible,  a  small  branch  of  hickory  and  one  of 
white  oak  above  and  below  each  of  the  rings  of  scars  already  mentioned 

(Sect.  77),  and  count  the 
rings  of  wood  above  and 
below  each  ring  of  scars. 

How  do  the  numbers 
correspond?  What  does 
this  indicate  ? 

Count  the  rings  of 
wood  on  the  cut-off  ends 
of  large  billets  of  some 
of  the  following  woods : 
locust,  chestnut,  syca- 
more, oak,  hickory. 

Do  the  successive  rings 
of  the  same  tree  agree  in 
thickness  ? 

Why?  or  why  not? 
Does  the  thickness  of 
the  rings  appear  uniform 
all  the  way  round  the  stick 
of  wood?  If  not,  the  rea- 
son in  the  case  of  an  up- 
right stem  (trunk)  is  per- 
haps that  there  was  a  greater  spread  of  leaves  on  the  side  where  the 
rings  are  thickest l  or  because  there  was  unequal  pressure,  caused  by 
bending  before  the  wind. 

Do  the  rings  of  any  one  kind  of  tree  agree  in  thickness  with 
those  of  all  the  other  kinds  ?     What  does  this  show  ? 
In  all  the  woods  examined  look  for  : 
(a)  Contrasts  in  color  between  the  hea,rtwood  and  the  sapwood.2 

1  See  Sect.  118. 

2  This  is  admirably  shown  in  red   cedar,  black  walnut,   barberry,  black 
locust  and  osage  orange. 


FIG.  71.  — Cross-Section  of  a  Three- Year-Old 

Linden  Twig.    (Much  magnified.) 
P,  epidermis  and  corky  layer  of  the  bark ;  Phi,  bast : 
C,  cambium  layer  ;  JR,  annual  rings  of  wood. 


STRUCTURE   OK  THE    S 


101 


(b)  The  narrow  lines  running  in  very  young  sterns  pretty  straight 
from  pith  to  bark,  in  older  wood  extending  only  a  little  of  the  way 
from  center  to  bark,  the  medullary  rays,  shown  in  Fig.  72. J 

(c)  The  wedge-shaped  masses  of  wood  between  these. 

(r/)  The  pores  which  are  so  grouped  as  to  mark  the  divisions 
between  successive  rings.     These  pores  indicate  the  cross-sections  of 

vessels  or  ducts.  Note  the  dis- 
tribution of  the  vessels  in  the 
rings  to  which  they  belong,  com- 


Fi<;.  7-2.  —  Cross-Section  of  Beech- Wood. 

b,  bark  ;  a,  flattened  cells  formed  near 
end  of  each  year's  growth  ;  w,  regu- 
lar wood-cells  ;  HI,  medullary  ray. 


FIG.  73.  —  Longitudinal  Section  of 
Mahogany  at  Eight  Angles  to 
Medullary  Rays,  showing  Cut- 
off Ends.  (Much  magnified.) 


pare  this  with  Figs.  58,  72,  and  decide  at  what  season  of  the  year 
the  largest  ducts  are  mainly  produced.  Make  a  careful  drawing 
of  the  end-section  of  one  billet  of  wood,  natural  size. 

Cut  off  a  grapevine  several  years  old  and  notice  the  great  size  of 


1  These  and  many  other  important  things  are  admirably  shown  in  the  thin 
wood-sections  furnished  for  $4  per  set  of  24  by  R.  B.  Hough,  Lowville,  N.  Y. 


102 


FOUNDATIONS   OF   BOTANY 


the  vessels.  Examine  the  smoothly  planed  surface  of  a  billet  of  red 
oak  that  has  been  split  through  the  middle  of  the  tree  (quartered 
oak),  and  note  the  large  shining  plates  formed 
by  the  medullary  rays. 

Look  at  another  stick  that  has  been  planed 
away  from  the  outside  until  a  good-sized  flat 
surface  is  shown,  and  see  how  the  medullary 
rays  are  here  represented  only  by  their 


FIG.  74.  —Formation  of 
a  Knot  in  a  Tree- 
Trunk. 


R,  cut-off  end  of  stick, 
showing  annual  rings ; 
K,  knot,  formed  by 
growth  of  a  branch. 


112.  Interruption  of  Annual  Rings  by 
Branches  ;  Knots.  —  When  a  leaf -bud  is 
formed  on  the  trunk  or  branch  of  a 
dicotyledonous  tree,  it  is  connected  with 
the  wood  by  nbro-vascular  bundles.  As 
the  bud  develops  into  a  branch,  the  few 
bundles  which  it  originally  possessed 
increase  greatly  in  number,  and  at 
length,  as  the  branch  grows,  form  a 
cylinder  of  wood  which  cuts  across  the 
annual  rings,  as  shown  in  Fig.  74. 


interruption  to  the  rings  is  a  knot, 
such  as  one  often  sees  in  boards  and 
planks.  If  the  branch  dies  long  before 
the  tree  does,  the  knot  may  be  buried  under  many  rings 
of  wood.  What  is  known  as  clear  lumber  is  obtained 
from  trees  that  have  grown  in  a  dense  forest,  so  that  the 
lower  branches  of  the  larger  trees  were  killed  by  the  shade 
many  years  before  the  tree  was  felled. 

In  pruning  fruit  trees  or  shade  trees  the  branches 
which  are  removed  should  be  cut  close  to  the  trunk.  If 
this  is  done,  the  growth  of  the  trunk  will  bury  the  scar 
before  decay  sets  in. 


STRUCTURE    OF   THE    STEM 


103 


113.    Comparison  of  the  Monocotyledonous  and  the  Dicotyledonous 

Stem.1 

MONOCOTYLEDONOUS  DICOTYLEDONOUS 

STEM  STEM 


General  Structure. 


A  hard  rind  of 
rather  uniform  struc- 
ture. Bundles  inter- 
mixed with  the  pith. 


Structure  of 
Bundles. 

Growth  in  Thick- 
ness. 


Bundles  closed, 
that  is,  without  per- 
manent cambium. 

Cells  of  mature 
parts  of  stem  expand 
somewhat,  but  (in 
most  palms)  new  ones 
are  not  found. 


A  complex  bark, 
usually  on  young 
shoots  consisting  of 
a  corky  layer,  a  green 
layer,  and  a  layer  of 
bast.  Wood  in  an- 
nual rings.  Pith  in 
a  cylinder  at  the  cen- 
ter. 

Bundles  open,  with 
permanent  cambium. 

New  wood-cells 
formed  throughout 
growing  season  from 
cambium  ring. 


114.    Review  Sketches  and  Diagrams. 

(1)  Monocotyledonous  stem  (lengthwise  section). 

(2)  Dicotyledonous  stem  (lengthwise  section). 

(3)  First  appearance  of  bundles  in  dicotyledonous  stem. 

(4)  Dicotyledonous  stem  five  years  or  more  old  (cross-section). 

(5)  Various  bark-cells. 

(6)  Various  cells  from  wood. 

(7)  Pith-cells. 

(8)  Collenchyma-cells. 


1  This  comparison  applies  only  to  most  of  the  woody  or  tree-like  stems. 


CHAPTER    VII 
LIVING    PARTS    OF   THE    STEM;    WORK    OF    THE    STEM 

115.  Active  Portions  of  the  Stems  of  Trees  and  Shrubs. 
—  In  annual  plants  generally  and  in  the  very  young 
shoots  of  shrubs  and  trees  there  are  stomata  or  breathing 
pores  which  occur  abundantly  in  the  epidermis,  serving 
for  the  admission  of  air  and  the  escape  of  moisture,  while 
the  green  layer  of  the  bark  answers  the  same  purpose  that 
is  served  by  the  green  pulp  of  the  leaf  (Chapter  XI). 
For  years,  too,  the  spongy  lenticels,  which  succeed  the 
stomata  and  occur  scattered  over  the  external  surface  of 
the  bark  of  trees  and  shrubs,  serve  to  admit  air  to  the 
interior  of  the  stem.  The  lenticels  at  first  appear  as 
roundish  spots,  of  very  small  size,  but  as  the  twig  or  shoot 
on  which  they  occur  increases  in  diameter  the  lenticel 
becomes  spread  out  at  right  angles  to  the  length  of  the 
stem,  so  that  it  sometimes  becomes  a  longer  transverse  slit 
or  scar  on  the  bark,  as  in  the  cherry  and  the  birch.  But 
in  the  trunk  of  a  large  tree  no  part  of  the  bark  except  the 
inner  layer  is  alive.  The  older  portions  of  the  bark,  such 
as  the  highly  developed  cork  of  the  cork-oak,  from  which 
the  ordinary  stoppers  for  bottles  are  made,  sometimes 
cling  for  years  after  they  are  dead  and  useless  except  as  a 
protection  for  the  parts  beneath  against  mechanical  injuries 
or  against  cold.  But  in  many  cases,  as  in  the  shell-bark  hick- 
ory and  the  grapevine,  the  old  bark  soon  falls  off  in  strips ; 
in  birches  it  finally  peels  off  in  bands  around  the  stem. 

104 


LIVING   PARTS   OF   THE    STEM  105 

The  cambium  layer  is  very  much  alive,  and  so  is  the 
young  outer  portion  of  the  wood.  Testing  this  "sap- 
wood,"  particularly  in  winter,  shows  that  it  is  rich  in 
starch  and  proteids. 

The  heartwood  of  a  full-grown  tree  is  hardly  living, 
unless  the  cells  of  the  medullary  rays  retain  their  vitality, 
and  so  it  may  be  that  wood  of  this  kind  is  useful  to  the 
tree  mainly  by  giving  stiffness  to  the  trunk  and  larger 
branches,  thus  preventing  them  from  being  easily  broken 
by  storms. 

It  is,  therefore,  possible  for  a  tree  to  flourish,  sometimes 
for  centuries,  after  the  heartwood  has  much  of  it  rotted 
away  and  left  the  interior  of  the  trunk  hollow,  as  shown 
in  Fig.  75. 

116.  Uses  of  the  Components  of  the  Stem There  is  a 

marked  division  of  labor  among  the  various  groups  of  cells 
that  make  up  the  stem  of  ordinary  dicotyledons,  particu- 
larly in  the  stems  of  trees,  and  it  will  be  best  to  explain 
the  uses  of  the  kinds  of  cells  as  found  in  trees,  rather  than 
in  herbaceous  plants.  A  few  of  the  ascertained  uses  of 
the  various  tissues  are  these: 

The  pith  forms  a  large  part  of  the  bulk  of  very  young 
shoots,  since  it  is  a  part  of  the  tissue  of  comparatively 
simple  structure  amid  which  the  fibro-vascular  bundles 
arise.  In  mature  stems  it  becomes  rather  unimportant, 
though  it  often  continues  for  a  long  time  to  act  as  a  store- 
house of  food. 

The  medullary  rays  in  the  young  shoot  serve  as  a  chan- 
nel for  the  transference  of  water  and  plant-food  in  a  liquid 
form  across  the  stem,  and  they  often  contain  much  stored 
food. 


106 


FOUNDATIONS  OF  BOTANY 


F!G.  75.  — Pioneer's  Cabin,  a  Very  Large  Hollow  Sequoia. 

The  vessels   carry  water  upward  and   (sometimes)  air 
downward  through  the  stem. 

The  wood-cells  of  the  heartwood  are  useful  only  to  give 


LIVING   PARTS   OF   THE    STEM  107 

stiffness  to  the  stem.  Those  of  the  sapwood,  in  addition 
to  this  work,  have  to  carry  most  of  the  water  from  the 
roots  to  the  leaves  and  other  distant  portions  of  the  plant. 

The  cambium  layer  is  the  region  in  which  the  annual 
growth  of  the  tree  takes  place  (Figs.  69,  71). 

The  most  important  portion  of  the  inner  bark  is  that 
which  consists  of  sieve-tubes,  for  in  these  digested  and 
elaborated  plant-food  is  carried  from  the  leaves  toward  the 
roots. 

The  green  layer  of  the  bark  in  young  shoots  does  much 
toward  collecting  nutrient  substances,  or  raw  materials, 
and  preparing  the  food  of  the  plant  from  air  and  water, 
but  this  work  may  be  best  explained  in  connection  with 
the  study  of  the  leaf  (Chapter  XI). 

117.  Movement  of  Water  in  the  Stem.  —  The  student 
has  already  learned  that  large  quantities  of  water  are  taken 
up  by  the  roots  of  plants. 

Having  become  somewhat  acquainted  with  the  structure 
of  the  stem,  he  is  now  in  a  position  to  investigate  the 
question  how  the  various  fluids,  commonly  known  as  sap, 
travel  about  in  it.1  It  is  important  to  notice  that  sap  is 
by  no  means  the  same  substance  everywhere  and  at  all 
times.  As  it  first  makes  its  way  by  osmotic  action  inward 
through  the  root-hairs  of  the  growing  plant  it  differs  but 
little  from  ordinary  spring  water  or  well  water.  The 
liquid  which  flows  from  the  cut  stem  of  a  "  bleeding " 
grapevine  which  has  been  pruned  just  before  the  buds 
have  begun  to  burst  in  the  spring,  is  mainly  water  with  a 
little  dissolved  mucilaginous  material.  The  sap  which  is 

1  See  the  paper  on  "  The  So-called  Sap  of  Trees  and  its  Movements,"  by 
Professor  Charles  R.  Barnes,  Science,  Vol.  XXI,  p.  535. 


108 


FOUNDATIONS   OF   BOTANY 


obtained  from  maple  trees  in  late  winter  or  early  spring, 
and  is  boiled  down  for  syrup  or  sugar,  is  still  richer  in 
nutritious  material  than  the  water  of  the  grapevine,  while 
the  elaborated  sap  which  is  sent  so  abundantly  into  the  ear 
of  corn,  at  its  period  of  filling  out,  or  into  the  growing 
pods  of  beans  and  peas,  or  into  the  rapidly  forming  acorn 
or  the  chestnut,  contains  great  stores  of  food,  suited  to  sus- 
tain plant  or  animal  life. 

EXPERIMENT   XXI 

Rise  of  Water  in  Stems.  —  Cut  some  short  branches  from  an 
apple  tree  or  a  cherry  tree  and  stand  the  lower  end  of  each 
in  red  ink;  try  the  same  experiment  with  twigs  of  oak,  ash, 
or  other  porous  wood,  and  after  some  hours l  examine  with 

the  magnifying  glass  and  with  the 
microscope,  using  the  2-inch  objective, 
successive  cross-sections  of  one  or  more 
twigs  of  each  kind.  Note  exactly  the 
portions  through  which  the  ink  has 
traveled.  Pull  off  the  leaves  from  one 
of  the  stems  after  standing  in  the  eosin 
solution,  and  notice  the  spots  on  the 
leaf-scar  through  which  the  eosin  has 
traveled.  These  spots  show  the  posi- 
tions of  the  leaf-traces,  or  fibre-vascular 
bundles,  connecting  the  stem  and  the 
leaf.  Repeat  with  several  potatoes,  cut 
crosswise  through  the  middle.  Try 
also  some  monocotyledonous  stems, 
such  as  those  of  the  lily  or  asparagus. 

For  the  sake  of  comparison  between 
FIG.  76.  —  A  Cutting  girdled  and 

sending  down  Root?  from  the      ™°ts   and  stems'   treat  ^   Convenient 
Upper  Edge  of  the  Girdled  Ring,     root,  such  as  a  parsnip,  in  the  same  way. 


1  If  the  twigs  are  leafy  and  the  room  is  warm,  only  from  5  to  30  minutes 
may  he  necessary. 


LIVING   PARTS    OF   THE    STEM 


109 


Examine  longitudinal  sections  of  some  of  the  twigs,  the  potatoes, 
and  the  roots.  In  drawing  conclusions  about  the  channels  through 
which  the  ink  has  risen  (those  through  which  the  newly  absorbed 
soil- water  most  readily  trav- 
els), bear  in  mind  the  fact 
that  a  slow  soakage  of  the 
red  ink  will  take  place  in 
all  directions,  and  therefore 
pay  attention  only  to  the 
strongly  colored  spots  or 
lines. 

What  conclusions  can  be 
drawn  from  this  experiment 
as  to  the  course  followed  by 
the  sap  ? 

From  the  familiar 
facts  that  ordinary  for- 
est trees  apparently 
flourish  as  well  after  the 
almost  complete  decay 
and  removal  of  their 
heartwood,  and  that 
many  kinds  will  live 
and  grow  for  a  consider- 

,  ,  »  .  j>     FIG.  77.  —  Channels    for   the    Movement    of 

able  time  alter  a  ring  ot  Water  upward  aild  downward. 

bark  extending  all  round     The  heavy  black  lines  in  roots,  stems,  and 
,  ,      ,  ,  leaves  show  the  course  of  the  tibro-vascular 

the  trunk  has  been  re-      bundles  through  which  the  principal  move- 
moved,  it  may  readily  be      ments  of  water  take  Place- 
inferred  that  the  crude  sap  in  trees  must  rise  through  some 
portion  of  the  newer  layers  of  the  wood.     A  tree  girdled 
by  the  removal  of  a  ring  of  sapwood  promptly  dies. 

118.    Downward  Movement  of   Liquids.  —  Most  dicoty- 
ledonous stems,  when  stripped  of  a  ring  of  hark  and  then 


110 


FOUNDATIONS   OF   BOTANY 


stood  in  water,  as  shown  in  Fig. 
bell-jar,  develop  roots  only  at  or 


76,  and  covered  with  a 
near  the  upper  edge  of 
the  stripped  portion,1 
and  this  would  seem  to 
prove  that  such  stems 
send  their  building  ma- 
terial —  the  elaborated 
sap  —  largely  at  any  rate 
down  through  the  bark. 
Its  course  is  undoubt- 
edly for  the  most  part 
through  the  sieve-cells 
(Figs.  63;  64),  which  are 
admirably  adapted  to 
convey  liquids.  In  ad- 
dition to  these  general 
upward  and  downward 
movements  of  sap,  there 
must  be  local  transfers 


FIG.  78.  —  Diagrammatic  Cross-Section  of  a 
Bundle  from  Sugar-Cane,  showing  Channels 
for  Air  and  Water.  (Magnified.) 

Air  travels  downward  through  the  two  large 
ducts  d  (and  the  two  smaller  ones  between 
them).  Water  travels  upward  through  the 
ducts  and  through  the  wood-cells  in  the 
region  marked  w.  Water  with  dissolved 
plant-food  travels  downward  through  the 
sieve-cells  in  the  region  marked  s. 

laterally  through  the  stem,  and 
these  are  at  times  of  much  im- 
portance to  the  plant. 

Since  the  liquid  building  mate- 
rial  travels    straight   down    the 

.  ..  FIG.  79.  —  Unequal  Growth  of  Kings 

Stem,     that    Side     Of    the    Stem    On      Of   Wood   in   nearly   Horizontal 
Which    the     manufacture    of    SUch       Stem  of  a  Juniper.  (Natural  size.) 

material  is  going  on  most  rapidly  should  grow  fastest. 

1  This  may  be  made  the  subject  of  a  protracted  class-room  experiment. 
Strong  shoots  of  willow  should  be  used  for  the  purpose. 


LIVIJS'G   PAUTS   OF   THE    STEM  111 

Plant-food  is  made  out  of  the  raw  materials  by  the  leaves, 
and  so  the  more  leafy  side  of  a  tree  forms  thicker  rings 
than  the  less  leafy  side,  as  shown  in  Fig.  79. 

119.  Rate  of  Movement  of  Water  in  the  Stem.  —  There 
are  many  practical  difficulties  in  the  way  of  ascertaining 
exactly  how  fast  the  watery  sap  travels  from  the  root  to 
the  leaves.  It  is,  however,  easy  to  illustrate  experimen- 
tally the  fact  that  it  does  rise,  and  to  give  an  approximate 
idea  of  the  time  required  for  its  ascent.  The  best  experi- 
ment for  beginners  is  one  which  deals  with  an  entire 
plant  under  natural  conditions. 

EXPERIMENT    XXII 

Wilting  and  Recovery.  —  Allow  a  fuchsia  or  a  hydrangea l  which 
is  growing  in  a  flower-pot  to  wilt  considerably  for  lack  of  watering. 
Then  water  it  freely  and  record  the  time  required  for  the  leaves  to 
begin  to  recover  their  natural  appearance  and  position,  and  the 
time  fully  to  recover. 

The  former  interval  of  time  will  give  a  very  rough  idea 
of  the  time  of  transfer  of  water  through  the  roots  and  the 
stem  of  the  plant.  From  this,  by  measuring  the  approxi- 
mate distance  traveled,  a  calculation  could  be  made  of  the 
number  of  inches  per  minute  that  water  travels  in  this 
particular  kind  of  plant,  through  a  route  which  is  partly 
roots,  partly  stem,  and  partly  petiole.  Still  another 
method  is  to  treat  leafy  stems  as  the  student  in  Exp.  XXI 
treated  the  twigs  which  he  was  examining,  and  note  care- 
fully the  rate  of  ascent  of  the  coloring  liquid.  This  plan 
is  likely  to  give  results  that  are  too  low,  still  it  is  of  some 
use.  It  has  given  results  varying  from  34  inches  per 

1  Hydrangea  Hortensia. 


112  FOUNDATIONS   OF  BOTANY 

hour  for  the  willow  to  880  inches  per  hour  for  the  sun- 
flower. A  better  method  is  to  introduce  the  roots  of  the 
plant  which  is  being  experimented  upon  into  a  weak 
solution  of  some  chemical  substance  which  is  harmless  to 
the  plant  and  which  can  readily  be  detected  anywhere  in 
the  tissues  of  the  plant  by  chemical  tests.  Proper  tests 
are  then  applied  to  portions  of  the  stem  which  are  cut 
from  the  plant  at  short  intervals  of  time. 

Compounds  of  the  metal  lithium  are  well  adapted  for 
use  in  this  mode  of  experimentation. 

120.  Causes  of  Movements  of  Water  in  the  Stem.  —  Some 
of  the  phenomena  of  osmosis  were  explained  in  Sect.  62, 
and  the  work  of  the  root-hairs  was  described  as  due  to 
osmotic  action. 

Root-pressure  (Sect.  66),  being  apparently  able  to  sus 
tain  a  column  of  water  only  80  or  90  feet  high  at  the 
most,  and  usually  less  than  half  this  amount,  would  be 
quite  insufficient  to  raise  the  sap  to  the  tops  of  the  tallest 
trees,  since  many  kinds  grow  to  a  height  of  more  than  100 
feet.  Our  Californian  "  big  trees,"  or  Sequoias,  reach 
the  height  of  over  300  feet,  and  an  Australian  species  of 
Eucalyptus,  it  is  said,  sometimes  towers  up  to  470  feet. 
Root-pressure,  then,  may  serve  to  start  the  soil-water  on 
its  upward  journey,  but  some  other  force  or  forces  must 
step  in  to  carry  it  the  rest  of  the  way.  What  these  other 
forces  are  is  still  a  matter  of  discussion  among  botanists. 

The  slower  inward  and  downward  movement  of  the  sap 
may  be  explained  as  due  to  osmosis.  For  instance,  in  the 
case  of  growing  wood-cells,  sugary  sap  descending  from  the 
leaves  into  the  stem  gives  up  part  of  its  sugar  to  form 
the  cellulose  of  which  the  wood-cells  are  being 


LIVING   PARTS   OF   THE    STEM  113 

This  loss  of  sugar  would  leave  the  sap  rather  more 
watery  than  usual,  and  osmosis  would  carry  it  from  the 
growing  wood  to  the  leaves,  while  at  the  same  time  a  slow 
transfer  of  the  dissolved  sugar  will  be  set  up  from  leaves 
to  wood.  The  water,  as  fast  as  it  reaches  the  leaves,  will 
be  thrown  off  in  the  form  of  vapor,  so  that  they  will 
not  become  distended  with  water,  while  the  sugar  will  be 
changed  into  cellulose  and  built  into  new  wood-cells  as  fast 
as  it  reaches  the  region  where  such  cells  are  being  formed. 

Plants  in  general l  readily  change  starch  to  sugar,  and 
sugar  to  starch.  When  they  are  depositing  starch  in  any 
part  of  the  root  or  stem  for  future  use,  the  withdrawal  of 
sugar  from  those  portions  of  the  sap  which  contain  it 
most  abundantly  gives  rise  to  a  slow  movement  of  dis- 
solved particles  of  sugar  in  the  direction  of  the  region 
where  starch  is  being  laid  up. 

121.  Storage  of  Food  in  the  Stem. — The  reason  why  the 
plant  may  profit  by  laying  up  a  food  supply  somewhere 
inside  its  tissues  has  already  been  suggested  (Sect.  91). 

The  most  remarkable  instance  of  storage  of  food  in  the 
stem  is  probably  that  of  sago-palms,  which  contain  an 
enormous  amount,  sometimes  as  much  as  800  pounds,  of 
starchy  material  in  a  single  trunk.  But  the  commoner 
plants  of  temperate  regions  furnish  plenty  of  examples  of 
deposits  of  food  in  the  stem.  As  in  the  case  of  seeds  and 
roots,  starch  constitutes  one  of  the  most  important  kinds 
of  this  reserve  material  of  the  stem,  and  since  it  is  easier 
to  detect  than  any  other  food  material  which  the  plant 
stores,  the  student  will  do  well  to  spend  time  in  looking 
for  starch  only. 

1  Not  including  most  of  the  ilowerless  and  very  !<>\v  ;uid  simple  kinds. 


114  FOUNDATIONS   OF   BOTANY 

Cut  thin  cross-sections  of  twigs  of  some  common  deciduous  tree 
or  shrub,  in  its  early  winter  condition,  moisten  with  iodine  solution, 
and  examine  for  starch  with  a  moderately  high  power  of  the  micro- 
scope. Sketch  the  section  with  a  pencil,  coloring  the  starchy  por- 
tions with  blue  ink,  used  with  a  mapping  pen,  and  describe  exactly 
in  what  portions  the  starch  is  deposited. 

122.  Storage  in  Underground  Stems. — The    branches 
and  trunk  of  a  tree   furnish  the  most  convenient  place 
in   which  to   deposit   food    during    winter  to  begin    the 
growth   of   the   following    spring.     But  in    those    plants 
which  die  down  to  the  ground  at  the  beginning  of  winter 
the    storage    must   be    either  in   the    roots,   as  has  been 
described   in   Sect.    58,   or    in    underground   portions    of 
the  stem. 

Rootstocks,  tubers,  and  bulbs  seem  to  have  been  de- 
veloped by  plants  to  answer  as  storehouses  through  the 
winter  (or  in  some  countries  through  the  dry  season)  for 
the  reserve  materials  which  the  plant  has  accumulated 
during  the  growing  season.  The  commonest  tuber  is  the 
potato,  and  this  fact  and  the  points  of  interest  which  it 
represents  make  it  especially  desirable  to  use  for  a  study 
of  the  underground  stem  in  a  form  most  highly  specialized 
for  the  storage  of  starch  and  other  valuable  products. 

123.  A  Typical  Tuber  :  the  Potato.  —  Sketch  the  general  outline 
of  a  potato,  showing  the  attachment  to  the  stem  from  which  it  grew.1 

Note  the  distribution  of  the  "eyes,"  — are  they  opposite  or  alter- 
nate ?  Examine  them  closely  with  the  magnifying  glass  and  then  with 
the  lowest  power  of  the  microscope.  What  do  they  appear  to  be  ? 

If  the  potato  is  a  stem,  it  may  branch,  —  look  over  a  lot  of  pota- 
toes to  try  to  find  a  branching  specimen.  If  such  a  one  is  secured, 
sketch  it. 

1  Examination  of  a  lot  of  potatoes  will  usually  discover  specimens  with  an 
inch  or  more  of  attached  stem. 


LIVING   PARTS   OF   THE   STEM  115 

Note  the  little  scale  overhanging  the  edge  of  the  eye,  and  see  if 
you  can  ascertain  what  this  scale  represents. 

Cut  the  potato  across,  and  notice  the  faint  broken  line  which 
forms  a  sort  of  oval  figure  some  distance  inside  the  skin. 

Place  the  cut  surface  in  eosin  solution,  allow  the  potato  to  stand 
so  for  many  hours,  and  then  examine,  by  slicing  off  pieces  parallel 
to  the  cut  surface,  to  see  how  far  and  into  what  portions  the  solution 
has  penetrated.  Refer  to  the  notes  on  the  study  of  the  parsnip 
(Sect.  56),  and  see  how  far  the  behavior  of  the  potato  treated  with 
eosin  solution  agrees  with  that  of  the  parsnip  so  treated. 

Cut  a  thin  section  at  right  angles  to  the  skin,  and  examine  with  a 
high  power.  Moisten  the  section  with  iodine  solution  and  examine 
again. 

If  possible,  secure  a  potato  which  has  been  sprouting  in  a  warm 
place  for  a  month  or  more  (the  longer  the  better),  and  look  near 
the  origins  of  the  sprouts  for  evidences  of  the  loss  of  material  from 
the  tuber. 

EXPERIMENT   XXIII 

Use  of  the  Corky  Layer.  —  Carefully  weigh  a  potato,  then  pare 
another  larger  one,  and  cut  portions  from  it  until  its  weight  is  made 
approximately  equal  to  that  of  the  first  one.  Expose  both  freely^to 
the  air  for  some  days  and  reweigh.  What  does  the  result  show  in 
regard  to  the  use  of  the  corky  layer  of  the  skin? 

124.  Morphology  of  the  Potato.  —  It  is  evident  that  in 
the  potato  we  nave  to  do  with  a  very  greatly  modified 
form  of  stem.  The  corky  layer  of  the  bark  is  well  repre- 
sented, and  the  loose  cellular  layer  beneath  is  very  greatly 
developed ;  wood  is  almost  lacking,  being  present  only  in 
the  very  narrow  ring  which  was  stained  by  the  red  ink, 
but  the  pith  is  greatly  developed  and  constitutes  the  prin- 
cipal bulk  of  the  tuber.  All  this  is  readily  understood  if 
we  consider  that  the  tuber,  buried  in  and  supported  by 
the  earth,  does  not  need  the  kinds  of  tissue  which  give 


116  FOUNDATIONS   OF   BOTANY 

strength,  but  only  those  which  are  well  adapted  to  store 
the  requisite  amount  of  food. 

125.  Structure  of  a  Bulb  ;   the  Onion.  —  Examine  the  external 
appearance  of  the  onion  and  observe  the  thin  membranaceous  skin 
which  covers  it.     This  skin  consists  of  the  broad  sheathing  bases  of 
the  outer  leaves  which  grew  on  the  onion  plant  during  the  summer. 
Remove  these  and  notice  the  thick  scales  (also  formed  from  bases 
of  leaves  as  shown  in  Fig.  48)  which  make  up  the  substance  of  the 
bulb. 

Make  a  transverse  section  of  the  onion  at  about  the  middle  and 
sketch  the  rings  of  which  it  is  composed.  Cut  a  thin  section  from 
the  interior  of  the  bulb,  examine  with  a  moderate  power  of  the 
microscope,  and  note  the  thin-walled  cells  of  which  it  is  composed. 

Split  another  onion  from  top  to  bottom  and  try  to  find : 

(a)  The  plate  or  broad  flattened  stem  inside  at  the  base  (Fig.  47). 

(&)  The  central  bud. 

(c)   The  bulb-scales. 

(c?)  In  some  onions  (particularly  large,  irregular  ones)  the  bulblets 
or  side  buds  arising  in  the  axes  of  the  scales  near  the  base. 

Test  the  cut  surface  for  starch. 

126,  Sugar  in  the  Onion Grrape  sugar  is  an  important 

substance  among  those  stored  for  food  by  the  plant.     It 
received  its    name    from  the  fact   that   it  was    formerly 
obtained   for   chemical    examination   from   grapes.      Old 
dry  raisins  usually  show  little  masses  of  whitish  material 
scattered  over  the  skin  which  are  nearly  pure  grape  sugar. 
Commercially  it  is   now  manufactured   on   an   enormous 
scale  from  starch  by  boiling  with  diluted  sulphuric  acid. 
In  the  plant  it  is  made  from  starch  by  processes  as  yet 
imperfectly  understood,  and  another  sugar,  called  maltose, 
is  made  from  starch  in  the  seed  during  germination. 

Both  grape  sugar  and  maltose  (and  hardly  any  other 
substances)  have  the  power  of  producing  a  yellow  or 


LIVING  PARTS   OF   THE   STEM  117 

orange  color  and  throwing  down  an  orange  or  reddish 
deposit,  when  they  are  added  to  a  brilliant  blue  alkaline 
solution  of  copper,  known  as  Felding**  solution.1  The 
color  cr  deposit  will  not  appear  until  the  solution  has 
been  heated  to  boiling. 

EXPERIMENT  XXIV 

Testing  for  Grape  Sugar.  —  Heat  to  boiling  in  a  test-tube  or  a 
small  beaker  some  weak  syrup  of  grape  sugar  or  some  honey,  much 
diluted  with  water.  Add  Fehling's  solution,  a  few  drops  at  a  time, 
until  a  decided  orange  color  appears.  Repeat  the  test  with  the 
water  in  which  some  slices  of  onion  have  been  boiled,  filtering  the 
water  through  a  paper  filter  and  heating  again  to  boiling  before 
adding  the  test  solution.2 

127.  Proteids  in  the  Onion.  —  Since   the   onion   grows 
so  rapidly  on  being  planted  in  the  spring,  there  must  be 
a  large  supply  of  food  in  the  bulb ;  there  may  be  other 
substances  present  besides  sugar. 

EXPERIMENT  XXV 

Testing  an  Onion  for  Other  Stored  Food.  —  Test  a  rather  thick 
slice  of  onion  by  heating  it  in  a  porcelain  evaporating  dish  with  a 
little  strong  nitric  acid  until  the  latter  begins  to  boil  and  the  onion 
becomes  somewhat  softened.8  Rinse  off  the  slice  of  onion  in  a  stream 
of  water,  then  pour  on  it  a  few  drops  of  ammonium  hydrate  and 
observe  any  change  of  color.  What  is  proved?  See  Sect.  29. 

128.  Tabular  Review  of  Experiments. 

[Continue  the  table  from  Sect.  74.] 

1  For  the  preparation  of  the  solution  see  Handbook. 

2  The  deposit  will  in  this  case,  even  if  orange  at  first,  finally  become  black, 
probably  owing  to  the  presence  of  sulphur  in  the  onion. 

8  Do  not  allow  the  acid  to  touch  the  clothing,  the  hands,  or  any  metallic 
object. 


118  FOUNDATIONS   OF  BOTANY 

129.    Review  Summary  of  Work  of  Stem. 


f  in  young  dicotyledonous  stems 
i  i] 


Channels  for  upward  movement  j  in   dicotyledonous    stems   several 
of  water  |       years  old 

li] 


in  monocotyledonous  stems 

Channels  for  downward  move-  f  in  dicotyledonous  stems       .     .     . 
ment  of  water  \  in  monocotyledonous  stems      .     . 

Channels  for  transverse  movements 

Rate  of  upward  movement 

C  where  stored 

Storage  of  plant-food  <  kinds  stored 


I 


uses 


CHAPTER    VIII 
BUDS 

130.  Structure  of  Buds.  —  While  studying  twigs  in  their 
winter  condition,  as  directed  in  Sects.  77,  78,  the  student 
had  occasion  to  notice  the  presence,  position,  and  arrange- 
ment of  buds  on  the  branch,  but  he  was  not  called  upon 
to  look  into  the  details  of  their  structure.    The  most  natu- 
ral time  to  do  this  is  just  before  the  study  of  the  leaf  is 
begun,  since  leafy  stems  spring  from  buds,  and  the  rudi- 
ments of  leaves  in  some  form  must  be  found  in  buds. 

131.  The  Horse-Chestnut  Bud.  —  Examine  one  of  the  lateral  buds 
on  a  twig  in  its  winter  or  early  spring  condition.1 

Make  a  sketch  of  the  external  appearance  of  the  buds  as  seen  with 
a  magnifying  glass. 

How  do  the  scales  with  which  it  is 
covered  lie  with  reference  to  those 
beneath  them? 

Notice  the  sticky  coating  on  the  scales. 

Are  the  scales 'opposite  or  alternate? 

Remove   the   scales   in  pairs,  placing  5 

them  in  order  on  a  sheet  of  paper,  thus  : 

Make  the  distance  from  1  to  1  as  much 
as  6  or  8  inches. 

How  many  pairs  are  found? 

Observe  as  the  scales  are  removed  whether  the  sticky  coating  is 

1  The  best  possible  time  for  this  examination  is  just  as  the  buds  are  begin- 
ning to  swell  slightly  in  the  spring.  The  bud  of  buckeye  or  of  cottonwood 
will  do  for  this  examination,  though  each  is  on  a  good  deal  smaller  scale  than 
the  horse-chestnut  bud.  Buds  may  be  forced  to  open  early  by  placing  twigs 
in  water  in  a  very  warm,  light  place  for  many  weeks. 

119 


-4 6 


-6 4- 


120 


FOUNDATIONS   OF  BOTANY 


thicker  on  the  outside  or  the  inside  of  each  scale,  and  whether  it 
is  equally  abundant  on  all  the  successive  pairs. 
What  is  the  probable  use  of  this  coating  ? 

Note  the  delicate  veining  of  some  of  the  scales  as  seen  through 

the  magnifying  glass.     What  does 
this  mean? 

Inside  the  innermost  pair  are 
found  two  forked  woolly  objects; 
what  are  these  ? 

Compare  with  Figs.  87  and  107. 
Their  shape  could  be  more  readily 
observed  if  the  woolly  coating  were 
removed. 

Can  you  suggest  a  use  for  the 
woolly  coating? 

Examine  a  terminal  bud  in  the 
same  way  in  which  you  have  just 
studied  the  lateral  bud. 

Does  it  contain  any  parts  not 
found  in  the  other? 

What  is  the  appearance  of  these 
parts  ? 

What  do  they  represent  ? 
If  there  is  any  doubt  about  their 
nature,  study  them  further  on  a 
horse-chestnut  tree  during  and  im- 
mediately after  the  process  of  leaf- 
ing out  in  the  spring. 

For  comparison  study  at  least  one 
Transitions   from   Bud-Scales    to    of  the  following  kinds    of  buds  in 

their  winter  or  early  spring  condi- 
tion :  hickory,  butternut,  beech,  ash,  magnolia  (or  tulip  tree),  lilac, 
balm  of  Gilead,  cottonwood,  cultivated  cherry.1 


FIG.  80.  —  Dissected  Bud  of  Buckeye 
macrostachyd),  showing 


1  Consult  the  account  of  the  mode  of  studying  buds  in  Professor  W.  F. 
Ganong's  Teaching  Botanist,  pp.  208-210.  If  some  of  the  buds  are  studied  at 
•  home,  pupils  will  have  a  better  chance  to  examine  at  leisure  the  unfolding 
process. 


BUDS 


121 


132,  Nature  of   Bud-Scales.  -  -  The 
fact  that  the  bud-scales  are  in  certain 
cases     merely     imperfectly    developed 
leaves    or   leaf-stalks    is    often    clearly 
manifest  from  the  series  of  steps  con- 
necting the  bud-scale  on  the  one  hand 
with  the  young  leaf  on  the  other,  which 
may  be  found  in  many  opening  buds, 
as    illustrated    by   Fig.   80.     In    other 
buds  the  scales  are  not  imperfect  leaves, 
but  the  little  appendages  (stipules,  Figs. 
98,  99)   which   occur  at  the   bases  of 
leaves.       This    kind    of    bud-scale    is 
especially  well  shown  in  the  magnolia 
and  the  tulip  tree. 

133.  Naked  Buds.  —  All  of  the  buds 
above  mentioned  are  winter  buds,  capa- 
ble of  living  through  the  colder  months 
of  the  year,  and  are  scaly  buds. 

In  the  herbs  of  temperate  climates, 
and  even  in  shrubs  and  trees  of  tropical 
regions,  the  buds  are  often  naked,  that 
is,  nearly  or  quite  destitute  of  scaly 
coverings  (Fig.  81). 

Make  a  study  of  the  naked  buds  of  any 
convenient  herb,  such  as  one  of  the  common 
"  geraniums"  (Pelargonium),  and  record  what 
you  find  in  it. 


134.    Position  of   Buds. 


fliq    FIG.  81.  —  Tip  of  Branch 
of  Ailanthus  in  Winter 


tinction  between   lateral   and   terminal    condition,  showing 

.          ,       ,  ,,      ,     ,     .  very  Large  Leaf-Scars 

buds  has  already  been  alluded  to.  and  nearly  Naked  Buds. 


122 


FOUNDATIONS   OF   BOTANY 


The  plumule  is  the  first  terminal  bud  which  the  plant 
produces.  Lateral  buds  are  usually  axillary,  as  shown  in 
Fig.  82,  that  is,  they  grow  in  the  angle  formed  by  the 
leaf  with  the  stem  (Latin  axilla,  armpit).  But  not  infre- 
quently there  are  several  buds  grouped  in  some  way  about 


FIG.  82.  —  Alternate  Leaves  of  Cultivated  Cherry,  with  Buds  in 
their  Axils,  in  October. 

a  single  leaf-axil,  either  one  above  the  other,  as  in  the 
butternut  (Fig.  84),  or  grouped  side  by  side,  as  in  the  red 
maple,  the  cherry,  and  the  box-elder  (Fig.  83). 

In  these  cases  all  the  buds  except  the  axillary  one  are 
called  accessory  or  supernumerary  buds. 

135.  Leaf-Buds  and  Flower-Buds ;  the  Bud  an  Undevel- 
oped Branch.  —  Such  buds  as  the  student  has  so  far 


BUDS 


123 


examined  for  himself  are  not  large  enough  to  show  in  the 
most  obvious  way  the  relation  of  the  parts  and  their  real 
nature. 

Fortunately,  it  is  easy  to  obtain  a  gigantic  terminal  bud 
which  illustrates  perfectly  the  structure  and  arrangement 
of   the    parts    of   buds    in 
general. 

Examine  and  sketch  a  rather 
small,  firm  cabbage,  preferably 
a  red  one,  which  has  been  split 
lengthwise  through  the  center l 
and  note 

(a)  The  short,  thick,  conical 
stem. 

(6)  The  crowded  leaves 
which  arise  from  the  stem,  the 
lower  and  outer  ones  largest 
and  most  mature,  the  upper 
and  innermost  ones  the  small- 
est of  the  series. 

(c)  The  axillary  buds,  found 
in  the  angles  made  by  some 
leaves  with  the  stem. 

Compare  the  section  of  the  cabbage  with  Fig.  86. 

Most  of  the  buds  so  far  considered  were  leaf-buds,  that 
is,  the  parts  inside  of  the  scales  would  develop  into  leaves, 
and  their  central  axes  into  stems;  but  some  were  mixed 
buds,  that  is,  they  contained  both  leaves  and  flowers  in  an 
undeveloped  condition. 

Flower-buds  contain  the  rudiments  of  flowers  only. 

Sometimes,  as  in  the  black  walnut  and  the  butternut, 
the  leaf-buds  and  flower-buds  are  readily  distinguishable 

1  Half  of  a  cabbage  will  be  enough  for  the  entire  division. 


FIG.  83.  —Accessory  Buds  of  Box-Elder 
(Negundo).    (Magnified.) 

A,  front  view  of  group. 

£,  two  groups  seen  in  profile. 


124 


FOUNDATIONS   OF  BOTANY 


by  their  difference  in  form,  while  in  other  cases,  as  in  the 
cultivated  cherry,  the  difference  in  form  is  but  slight. 
The  rings  of  scars  about  the  twig,  shown  in  Figs.  82 
and  85,  mark  the  place  where  the  bases 
of   bud-scales   were   attached.     A  little 
examination    of   the    part   of    the   twig 
which  lies  outside  of  this  ring,  as  shown 
in  Fig.  82,  will  lead  one  to  the  conclu- 
sion that  this  portion  has  all  grown  in 
the  one  spring  and  summer  since  the 
bud-scales  of  that  particular  ring  dropped 
off.     Following  out  this  suggestion,  it  is 
easy  to  reckon  the   age   of  any  moder- 
ately old  portion  of  a  branch,  since  it  is 
a'  Hi1  equal  to  the  number  of  segments  between 

the  rings.  In  rapidly  growing  shoots  of 
willow,  poplar,  and  similar  trees,  5  or  10 
feet  of  the  length  may  be  the  growth  of 
a  single  year,  while  in  the  lateral  twigs 
of  the  hickory,  apple,  or  cherry  the  yearly 
increase  may  be  but  a  fraction  of  an  inch. 
Such  fruiting  "  spurs  "  as  are  shown  in 
Fig.  85  are  of  little  use  in  the  permanent 

FIG.  84. -Accessory     growth    Qf    tne    tree?    an(J    poplars,    elms, 


soft   maples   and   other   trees  shed   the 
these  every  year.      Whatever 


Buds  of  Butternut. 
(Reduced.) 

I,  leaf-scar  ;  ax,  axil- 
lary bud ;  a,  a',  ac- 
cessory buds;  t,  the  amount  of  this  growth,  it  is  but  the 

lengthening  out  and  development  of  the 
bud,  which  may  be  regarded  as  an  undeveloped  stem  or 
branch,  with  its  internodes  so  shortened  that  successive 
leaves  seem  almost  to  spring  from  the  same  point. 


BUDS 


125 


136.  Vernation.  —  Procure  a  considerable  number  of  buds  which 
are  just  about  to  burst,  and  others  which  have  begun  to  open.  Cut 
each  across  with  a  razor  or  very  sharp  scalpel ;  examine  first  with 
the  magnifying  glass,  and  then  with  the  lowest  power  of  the  micro- 
scope. Pick  to  pieces  other  buds  of  the  same 
kinds  under  the  magnifying  glass,  and  report 
upon  the  manner  in  which  the  leaves  are 
packed  away. 

The  arrangement  of  leaves  in  the 
bud  is  called  vernation;  some  of  the 
principal  modes  are  shown  in  Fig.  86. 


.    sc 


f 


-1900 
— -1899 


FIG.  85.  —A  slowly  grown  Twig 
of  Cherry,  3  inches  long  and 
about  ten  years  old. 

The  pointed  bud  I  is  a  leaf -bud ; 
the  more  obtuse  accessory 
buds  /,  /  are  flower-buds. 


FIG.  86. 

-B,  a  twig  of  European  elm  ;  A,  a  longitudi- 
nal sectlH  of  the  buds  of  B  (considerably 
magnifiech  ;  ax,  the  axis  of  the  bud,  which 
will  elongate  into  a  shoot ;  sc,  leaf-scars. 


In  the  cherry  the  two  halves  ojF  the  leaf  are  folded 
together  flat,  with  the  under  surfaces  outward  ;  in  the 
walnut  the  separate  leaflets,  or  parts  of  the  leaf,  are  folded 


126 


FOUNDATIONS   OF  BOTANY 


flat  and  then  grouped  into  a  sort  of  cone  ;  in  the  snow- 
ball each  half  of  the  leaf  is  plaited  in  a  somewhat  fan-like 
manner,  and  the  edges  of  the  two  halves  are  then  brought 
round  so  as  to  meet;  in  the  lady's  mantle  the  fan-like 
plaiting  is  very  distinct;  in  the  wood  sorrel  each  leaflet 


FIG.  87, 1.  — Types  of  Vernation. 
1,  2,  Cherry  ;  3,  4,  European  walnut ;  5,  6,  snowball ;  7,  lady's  mantle  ;  8,  oxalis. 

is  folded  smoothly,  and  then  the  three  leaflets  packed 
closely  side  by  side.  All  these  modes  of  vernation  and 
many  others  have  received  accurate  descriptive  names  by 
which  they  are  known  to  botanists. 

137.    Importance  of  Vernation.  — The  significance  of  ver- 
nation is  best  understood  by  considering  that  there  are  two 


BUDS 


127 


important  purposes  to  be  served ;  the  leaves  must  be 
stowed  as  closely  as  possible  in  the  bud,  and  upon  begin- 
ning to  open  they  must  be  protected  from  too  great  heat 
and  dryness  until  they  have  reached  a  certain  degree  of 
firmness.  It  may  be  inferred  from  Fig.  87,  I,  that  it  is 
common  for  very  young  leaves  to  stand  vertically.  This 
protects  them  considerably  from  the  scorching  effect  of  the 
sun  at  the  hottest  part  of  the  day.  Many  young  leaves, 
as,  for  instance,  those  of  the  silver-leafed  poplar,  the  pear, 
the  beech,  and  the  mountain  ash,  are  sheltered  and  pro- 


BCD 

FIG.  87,  II.  —  Development  of  an  Oxalis  Leaf. 

A,  full-grown  leaf ;  B,  rudimentary  leaf,  the  leaflets  not  yet  evident ;  C,  more 
advanced  stage,  the  leaflets  appearing ;  D,  a  still  more  advanced  stage  ; 
B,  C,  and  D,  considerably  magnified. 

tected  from  the  attacks  of  small  insects  by  a  coating  of 
wool  or  down,  which  they  afterwards  lose.  Those  of  the 
tulip  tree  are  enclosed  for  a  little  time  in  thin  pouches, 
which  serve  as  bud-scales,  and  thus  entirely  shielded  from 
direct  contact  with  the  outside  air  (see  Sect.  117). 

138.  Dormant  Buds.  —  Generally  some  of  the  buds  on  a 
branch  remain  undeveloped  in  the  spring,  when  the  other 
buds  are  beginning  to  grow,  and  this  inactive  condition 
may  last  for  many  seasons.  Finally  the  bud  may  die,  or 
some  injury  to  the  tree  may  destroy  so  many  other  buds 
as  to  leave  the  dormant  ones  an  extra  supply  of  food,  and 


128  FOUNDATIONS   OE  BOTANY 

this,  with  other  causes,  may  force  them  to  develop  and  to 
grow  into  branches. 

Sometimes  the  tree  altogether  fails  to  produce  buds  at 
places  where  they  would  regularly  occur.  In  the  lilac  the 
terminal  bud  usually  fails  to  appear,  and  the  result  is  con- 
stant forking  of  the  branches. 

139.  Adventitious  Buds.  —  Buds  which  occur  in  irregu- 
lar places,  that  is,  not  terminal  nor  in  or  near  the  axils  of 
leaves,  are  called  adventitious  buds  ;  they  may  spring  from 
the  roots,  as  in  the  silver-leafed  poplar,  or  from  the  sides 
of  the  trunk,  as  in  our  American  elm.  In  many  trees,  for 
instance  willows  and  maples,  they  are  sure  to  appear  after 
the  trees  have  been  cut  back.  Willows  are  thus  cut  back 
or  pollarded,  as  shown  in  Plate  II,  in  order  to  cause  them 
to  produce  a  large  crop  of  slender  twigs  suitable  for 
basket-making. 

Leaves  rarely  produce  buds,  but  a  few  kinds  do  so  when 
they  are  injured.  Those  of  the  bryophyllum,  a  plant  allied 
to  the  garden  live-for-ever,  when  they  are  removed  from 
the  plant  while  they  are  still  green  and  fresh,  almost  always 
send  out  buds  from  the  margin.  These  do  not  appear  at 
random  but  are  borne  at  the  notches  in  the  leaf-margin  and 
are  accompanied  almost  from  the  first  by  minute  roots. 

Pin  up  a  bryophyllum  leaf  on  the  wall  of  the  room  or 
lay  it  on  the  surface  of  moist  earth,  and  follow,  day  by  day, 
the  formation  and  development  of  the  buds  which  it  may 
produce. 

This  plant  seems  to  rely  largely  upon  leaf-budding  to 
reproduce  itself,  for  in  a  moderately  cool  climate  it  rarely 
flowers  or  seeds,  but  drops  its  living  leaves  freely,  and  from 
each  such  leaf  one  or  several  new  plants  may  be  produced. 


PLATE  II.  —  Pollarded  Willows 


BUDS  129 

140.    Review  Summary  of  Chapter  VIII. 

Coverings 

BudsJ  leaf-buds 

Contents    .     .     J  flower-buds 

I  mixed  buds 


regular 
Classes  of  buds  as  re- 


gards position  .  .     . 


irregular 


Make  a  sketch  of  Fig.  82  as  it  looked  in  June  of  the  same  sum- 
mer ;  also  as  it  would  look  the  following  June.  Sketch  the  twigs  of 
Fig.  30  and  Fig.  86  as  seen  one  year  later. 


CHAPTER   IX 
LEAVES 

141.  The  Eljn  Leaf.  —  Sketch  the  leafy  twig  of  elm.  that  is  sup- 
plied to  you.1 

Report  on  the  following  points  : 

(a)  How  many  rows  of  leaves  ? 

(&)  How  much  overlapping  of  leaves  when  the  twig  is  held  with 
the  upper  sides  of  the  leaves  toward  you  ?  Can  you  suggest  a  reason 
for  this  ?  Are  the  spaces  between  the  edges  of  the  leaves  large  or 
small  compared  with  the  leaves  themselves  ? 

Pull  off  a  single  leaf  and  make  a  very  careful  sketch  of  its  under 
surface,  about  natural  size.  Label  the  broad  expanded  part  the  Hade, 
and  the  stalk  by  which  it  is  attached  to  the  twig,  leaf-stalk  or  petiole. 

Study  the  outline  of  the  leaf  and  answer  these  questions : 

(a)  What  is  the  shape  of  the  leaf  taken  as  a  whole  ?  (See  Fig. 
88.)  Is  the  leaf  bilaterally  symmetrical,  i.e.,  is  there  a  middle  line 
running  through  it  lengthwise,  along  which  it  could  be  so  folded 
that  the  two  sides  would  precisely  coincide  ? 

(6)  What  is  the  shape  of  the  tip  of  the  leaf?     (See  Fig.  89.) 

(c)  Shape  of  the  base  of  the  leaf?     (See  Fig.  90.) 

(d)  Outline  of  the  margin  of  the  leaf?     (See  Fig.  93.) 

Notice  that  the  leaf  is  traversed  lengthwise  by  a  strong  midrib 
and  that  many  so-called  veins  run  from  this  to  the  margin.  Are 

1  Any  elm  will  answer  the  purpose.  Young  strong  shoots  which  extend 
horizontally  are  best,  since  in  these  leaves  are  most  fully  developed  and  their 
distribution  along  the  twig  appears  most  clearly.  Other  good  kinds  of  leaves 
with  which  to  begin  the  study,  if  elm  leaves  are  not  available,  are  those  of 
beech,  oak,  willow,  peach,  cherry,  apple.  Most  of , the  statements  and  direc- 
tions above  given  would  apply  to  any  of  the  leaves  just  enumerated.  If  this 
chapter  is  reached  too  early  in  the  season  to  admit  of  suitable  material  being 
procured  for  the  study  of  leaf  arrangement,  that  topic  may  be  omitted  until 
the  leaves  of  forest  trees  have  sufficiently  matured. 

130 


LEAVES 


131 


FIG.  88.  —  General  Outline  of  Leaves. 

a,  linear ;  6,  lanceolate  ;  c,  wedge-shaped  ;  d,  spatulate  ;  e,  ovate  ;  f,  obovate  ; 
g,  kidney-shaped  ;  h,  orbicular  ;  i,  elliptical. 


a,  acuminate  or  taper-pointed  ;  6,  acute  ;  c,  obtuse  ;  d,  truncate  ;  e,  retuse  ;  /, 
emarginat  j  or  notched  ;  g  (end  leaflet),  obcordate  ;  h,  cuspidate,  — the  point 
sharp  ar  ±  rigid  ;  i ,  mucronate ,  —  the  point  merely  a  prolongation  of  the  midrib. 


132 


FOUNDATIONS  OF  BOTANY 


FIG.  90.  —  Shapes  of  Bases  of  Leaves. 


1,  heart-shaped  (uusymmetrically) ;  2,  arrow- 
shaped;  3,  halberd-shaped. 


FIG.  91.  —Peltate  Leaf  of 
Tropaeolum. 


FIG.  92. 

A,  runoinate  leaf  of  dandelion ;  B, 
lyrate  leaf. 


FIG.  93.  —  Shapes  of  Margins 

of  Leaves. 

a  (1),  finely  serrate  ;  (2),  coarsely 
serrate;  (3),  doubly  serrate. 
6  (1),  finely  dentate  ;  (2) ,  sinuate 
dentate;  (3),  doubly  dentate. 
c,  deeply  shrrate.  d,  wavy. 
e  (1),  crenate  or  Vcalloped ;  (2), 
doubly  crenate. 


LEAVES 


133 


these  veins  parallel  ?  Hold  the  leaf  up  towards  the  light  and  see 
how  the  main  veins  are  connected  by  smaller  veinlets.  Examine 
with  your  glass  the  leaf  as  held  to  the  light 
and  make  a  careful  sketch  of  portions  of 
one  or  two  veins  and  the  intersecting  vein- 
lets.  How  is  the  course  of  the  veins  shown 
on  the  upper  surface  of  the  leaf  ? 

Examine  both  surfaces  of  the  leaf  with 
the  glass  and  look  for  hairs  distributed  on 
the  surfaces.  Describe  the  manner  in  which 
the  hairs  are  arranged. 


FIG.  94.— Netted  Vein- 
ing  (pinnate)  in  the 
Leaf  of  the  Foxglove. 


The  various  forms  of  leaves  are 
classed  and  described  by  botanists  with 
great  minuteness,1  not  simply  for  the 
study  of  leaves  themselves,  but  also 
because  in  classifying  and  describing 
plants  the  characteristic  forms  of  the 
leaves  of  many  kinds  of  plants  form 
a  very  simple 
and  ready 

means    of    distinguishing    them 

from  each  other  and  identifying 

them.     The  student  is  not  ex- 
pected to  learn  the  names  of  the 

several   shapes   of   leaves    as   a 

whole  or  of  their  bases,  tips,  or 

margins,  except  in  those   cases 

in  which  he  needs  to  use  and 

apply  them. 

Many  of  the  words  used  to  describe  the  shapes  of  leaves 

are  equally  applicable  to  the  leaf-like  parts  of  flowers. 


FIG.  95.— Netted  Veining  (pal- 
mate) in  Leaf  of  Melon. 


1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  pp.  623-637. 


134 


FOUNDATIONS   OF  BOTANY 


142.    The  Maple  Leaf.  —  Sketch  the  leafy  twig. 
Are  the  leaves  arranged  in  rows  like  those  of  the  elm?     How  are 
they  arranged? 

How  are  the  petioles  distorted  from  their  natural  positions  to 
bring  the  proper  surface  of  the  leaf  upward  toward  the  light? 

Do  the  edges  of  these  leaves  show  larger  spaces  between  them 
than  the  elm.  leaves  did,  i.e.,  would  a  spray  of  maple  intercept  the 
sunlight  more  or  less  perfectly  than  a  spray  of 
elm  ?     Pull  off  a  single  leaf  and  sketch  its  lower 
surface,  about  natural  size. 

Of  the  two  main   parts  whose  names  have 
already  been  learned  (blade  and  petiole),  which 
is  more  developed  in  the  maple   than  in   the 
elm  leaf? 
Describe  : 

(a)  The  shape  of  the  maple  leaf  as  a  whole. 
To  settle  this,  place  the  leaf  on  paper,  mark  the 
positions  of  the  extreme  points  and  connect 
these  by  a  smooth  line. 

Z>     Its  outline  as  to  main  divisions  :  of  what 


FIG.  96.  — Pinnately 

Divided   Leaf   of 

Celandine. 
The  blade  of  the  leaf  is    kind  and  how  many. 

discontinuous,    con-         (c)   The    detailed 


sisting  of  several  por-     x-p-       ng\ 


outline    of     the    margin 


tions  between  which 
are  spaces  in  which 
one  part  of  the  blade 
has  been  developed. 


Compare  the  mode  of  veining  or  venation  of 
the    elm    and    the    maple    leaf    by   making    a 
diagram  of  each. 
These  leaves  agree  in  being  netted-veined  ;  i.e.,  in  having  veinlets 
that  join  each  other  at  many  angles,  so  as  to  form  a  sort  of  delicate 
lace-work,  like  Figs.  94  and  95. 

They  differ,  however,  in  the  arrangement  of  the  principal  veins.  Such 

a  leaf  as  that  of  the  elm  is  said  to  be  feather-veined,  orpinnately  veined. 

The  maple  leaf,  or  any  leaf  with  closely  similar  venation,  is  said  to 

be  palmately  veined.     Describe  the  difference  between  the  two  plans 

of  venation. 

143.   Relation  of  Venation  to  Shape  of  Leaves.  —  As  soon 
as  the  student  begins  to  observe  leaves  somewhat  widely, 


LEAVES 


135 


he  can  hardly  fail  to  notice  that  there  is  a  general  relation 
between  the  plan  of  venation  and  the  shape  of  the  leaf. 
How  may  this  relation  be  stated?  In  most  cases  the 
principal  veins  follow  at  the  outset  a  pretty  straight 
course,  a  fact  for  which  the  student  ought  to  be  able  to 
give  a  reason  after  he  has  performed  Exp.  XXXII. 

On  the  whole,  the  arrangement  of  the 
veins  seems  to  be 
such  as  to  stiff- 
en the  leaf 
most  in  the 
parts  that  need 


Fro.  97.  — Palmately  Divided 
Leaf  of  Buttercup. 


FIG.  98.— Leaf  of  Ap- 
ple, with  Stipules. 


FIG.  99.  —  Leaf  of 
Pansy,  with  Leaf- 
Like  Stipules. 


most  support,  and  to  reach  the  region  near  the  margin  by 
as  short  a  course  as  possible  from  the  end  of  the  petiole. 

144.  Stipules.  —  Although  they  are  absent  from  many 
leaves,  and  disappear  early  from  others,  stipules  form  a 
part  of  what  the  botanist  regards  as  an  ideal  or  model 
leaf.1  When  present  they  are  sometimes  found  as  little 

1  Unless  the  elm  twigs  used  in  the  previous  study  were  cut  soon  after  the 
unfolding  of  the  leaves  in  spring,  the  stipules  may  not  have  been  left  in  any 
recognizable  shape. 


136 


FOUNDATIONS  OF  BOTANY 


bristle-shaped  objects  at  the  base  of  the  leaf,  as  in  the 
apple  leaf  (Fig.  98),  sometimes  as  leaf-like  bodies,  for 
example  in  the  pansy  (Fig.  99),  and  in 
many  other  forms,  one  of  which  is  that 
of  spinous  appendages,  as  shown  in  the 
common  locust  (Fig.  103). 

145.  Parallel -Veined  Leaves.  —  The 
leaves  of  many  great  groups  of  plants, 
such  as  the  lilies,  the  sedges,  and  the 
grasses,  are  commonly  parallel-veined, 
that  is,  with  the  veins  running  nearly 
parallel,  lengthwise  through  the  blade, 

PIG.  100.  —  Parallel- 
Veined  Leaf  of  Sol-     as  shown  in  Fig.  100,  or 

with  parallel  veins  pro- 
ceeding from  a  midrib  and  thence  extend- 
ing to  the  margin,  as  shown  in  Fig.  101. 

146.  Occurrence  of  Netted  Veining  and 
of  Parallel  Veining.  —  The  student  has 
already,  in  his  experiments  on  germina- 
tion, had  an  opportunity  to  observe  the 
difference  in  mode  of  veining  between 
the  leaves  of  some  dicotyledonous  plants 
and  those  of  monocotyledonous  plants. 
This  difference  is  general  throughout 
these  great  groups  of  flowering  plants. 
What  is  the  difference? 

The  polycotyledonous  pines,  spruces,  no.  101.  -  Parallel 
and   other   coniferous  trees   have  leaves     ve£™runniSom 
with  but  a  single  vein,  or  two  or  three     midrib  to  margin< 
parallel  ones,  but  in  their  case  the  veining  could  hardly 
be  other  than  parallel,  since  the  needle-like  leaves  are  so 


LEAVES 


137 


narrow  that  no  veins  of  any  considerable  length  could 
exist  except  in  a  position  lengthwise  of  the  leaf. 

The  fact  that  a  certain  plan  of  venation  is  found  mainly 
in  plants  with  a  particular  mode  of  germination,  of  stem 
structure,  and  of  arrangement  of  floral  parts,  is  but  one 
of  the  frequent 
cases  in  botany 
in  which  the 
structures  of 
plants  are  corre- 
lated in  a  way 
which  it  is  not 
easy  to  explain. 

No  one  knows 
why  plants  with 
two  cotyledons 

should    have       ^v  i      \ ;  m,  if 

,  ^    -  j&    \\     "^ 

n  e  1 1  e  d- v  e  i  n  e  d 

leaves,  but  many 
such  facts  as  this 
are  familiar  to 
every  botanist. 

147.  Simple 
and  Compound 
Leaves.  —  The 
leaves  so  far  studied  are  simple  leaves,  that  is,  leaves  of  which 
the  blades  are  more  or  less  entirely  united  into  one  piece. 
But  while  in  the  elm  the  margin  is  cut  in  only  a  little 
way,  in  some  maples  it  is  deeply  cut  in  toward  the  bases 
of  the  veins.  In  some  leaves  the  gaps  between  the 
adjacent  portions  extend  all  the  way  down  to  the  petiole 


FIG.  102.  —  The  Fall  of  the  Horse-Chestnut  Leaf. 


138 


FOUNDATIONS   OF  BOTANY 


(in  palmately  veined  leaves)  or  to  the  midrib  (in  pinnately 

veined  ones).     Such  divided  leaves  are  shown  in  Figs. 

96  and  97. 

In  still  other  leaves,  known   as  compound  leaves,  the 

petiole,  as  shown  in  Fig.  102  (palmately  compound),  or  the 
midrib,  as  shown  in  Fig.  103  (pin- 
nately compound),  bears  what  look  to 
be  separate  leaves.  These  differ  in 
their  nature  and 
mode  of  origin 
from  the  portions 
of  the  blade  of  a 
divided  leaf.  One 
result  of  this  dif- 
ference appears  in 
the  fact  that  some 
time  before  the 
whole  leaf  is  ready 
to  fall  from  the 
tree  or  other  plant 
in  autumn,  the 
separate  portions 
or  leaflets  of  a 
compound  leaf  are 


FlQ.  103.  —  Pinnately  Com- 
pound Leaf  of  Locust, 
with  Spines  for  Stipules. 


FIG.  104.  — Pinnately 
Compound  Leaf  of 

Pea.    A  tendril  takes  .        ... 

the  place  of  a  terminal      Seen  to    be  jointed 
leaflet. 


at  their  attach- 
ments, just  as  whole  leaves  are  to  the  part  of  the  stem  from 
which  they  grow.  In  Fig.  102  the  horse-chestnut  leaf  is 
shown  at  the  time  of  falling,  with  some  of  the  leaflets 
already  disjointed. 

That  a  compound  leaf,   in  spite  of  the  joints  of  the 


LEAVES  139 

separate  leaflets,  is  really  only  one  leaf  is  shown  :   (1)  by 
the  absence  of  buds  in  the  axils  of  leaflets  (see  Fig.  82)  ; 

(2)  by  the  arrangement  of  the  blades  of  the  leaflets  hori- 
zontally, without  any  twist  in  their  individual  leaf-stalks  ; 

(3)  by  the  fact  that  their  arrangement  on  the  midrib  does 
not  follow  any  of  the  systems  of  leaf  arrangement  on  the 
stem  (Sect.  149).     If  each  leaflet  of  a  compound  leaf  should 
itself  become  compound,  the  result  would  be  to  produce 
a  twice  compound  leaf.     Fig.  113  shows  that  of  an  acacia. 
What  would  be  the  appearance  of  a  thrice  compound  leaf? 

148.    Review  Summary  of  Leaves.1 

f1- 

Parts  of  a  model  leaf     ...  Jo 


Classes  of  netted-veined  leaves 


Classes  of  parallel-veined  leaves 


Relation  of  venation  to  number  of  cotyledons     .     .     .     .  J 
*  I 

Compound  leaves ;  — types,  dependent  on  arrangement  of  Jl. 

leaflets 1  2. 


Once,  twice,  or  three  times  compound  .... 
1  Illustrate  by  sketches  if  possible. 


CHAPTER   X 


LEAF  ARRANGEMENT  FOR  EXPOSURE  TO  SUN  AND  AIR; 
MOVEMENTS   OF  LEAVES  AND   SHOOTS 

149.    Leaf  Arrangement.1  —  As  has  been  learned  from 
the  study  of  the  leafy  twigs  examined,  leaves  are  quite 

generally  arranged  so  as  to 
secure  the  best  possible  ex- 
posure to  the  sun  and  air. 
This,  in  the  vertical  shoots 
of  the  elm,  the  oak  (Fig.  105), 
the  apple,  beech,  and  other 
alternate-leaved  trees,  is  not 
inconsistent  with  their  spiral 
arrangement  of  the  leaves 

FIG.  105.  —  Leaf  Arrangement 
of  the  Oak. 

around  the  stem.  In  horizon- 
tal twigs  and  branches  of  the 
elm,  the  beech  (Fig.  106), 
the  chestnut,  the  linden,  and 
many  other  trees  and  shrubs, 
the  desired  effect  is  secured 
by  the  arrangement  of  all  the 
leaves  in  two  flat  rows,  one  on  each  side  of  the  twig. 


FIG.  106.  — Leaf  Arrangement  of 
European  Beech. 


1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  pp.  396-424. 

140 


PLATE  III.  —  Exposure  to  Sunlight,  Japanese  Ivy 


LEAF  EXPOSURE  TO  SUN  AND  AIR 


141 


FIG.  107.— Leaf  Arrangement  of  Horse-Chestnut  on 
Vertical  Shoots  (top  view). 


The  rows  are  produced,  as  it  is  easy  to  see  on  examining 
such  a  leafy  twig,  by  a  twisting  about  of  the  petioles. 

The  adjustment 
in  many  opposite- 
leaved  trees  and 
shrubs  consists  in 
having  each  pair 
of  leaves  cover 
the  spaces  be- 
tween the  pair 
below  it,  and 
sometimes  in  the 
lengthening  of 
the  lower  petioles 
so  as  to  bring 
the  blades  of 
the  lower  leaves  outside  those  of  the  upper  leaves.  Ex- 
amination of  Figs.  107  and  108  will  make  the  matter 
clear. 

The    student 
should  not  fail  to 
study  the  leafage 
of  several  trees  of     jf5g 
different  kinds  on    *    ^ 
the  growing  tree 
itself,  and  in 
climbers  on  walls 
(Plate  III),  and  to 
notice  how  circum- 
stances modify  the  position  of  the  leaves.    Maple  leaves,  for 
example,  on  the  ends  of  the  branches  are  arranged  much 


FIG.  108.— Leaf  Arrangement  of  Horse-Chestnut 
on  Vertical  Shoots  (side  view). 


142 


FOUNDATIONS   OF  BOTANY 


like  those  of  the  horse-chestnut,  but  they  are  found  to  be 
arranged  more  nearly  flatwise  along  the  inner  portions 
of  the  branches,  that  is,  the  portions  nearer  the  tree. 
Figs.  109  and  110  show  the  remarkable  difference  in 
arrangement  in  different  branches  of  the  Deutzia,  and 
equally  interesting  modifications  may  be  found  in 
alternate-leaved  trees,  such  as  the  elm  and  the  cherry. 


FIG.  109.  — Opposite  Leaves  of  Deutzia1  (from  the  same  shrub  as  Fig.  110),  as 
arranged  on  a  Horizontal  Branch. 

150.  Leaf -Mosaics.  —  In  very  many  cases  the  leaves  at 
the  end  of  a  shoot  are  so  arranged  as  to  form  a  pretty 
symmetrical  pattern,  as  in  the  horse-chestnut  (Fig.  107). 
When  this  is  sufficiently  regular,  usually  with  the  space 
between  the  leaves  a  good  deal  smaller  than  the  areas  of 
the  leaves  themselves,  it  is  called  a  leaf -mosaic  (Fig.  111). 
Many  of  the  most,  interesting  leaf -groups  of  this  sort  (as 

1  Deutzia  crenata. 


LEAF  EXPOSURE   TO   SUN  AND   AIR 


143 


FIG.  110.  — Opposite  Leaves  of  Deutzia,  as 
arranged  on  a  Vertical  Branch. 


in  the  figure  above  mentioned)  are  found  in  the  so-called 
root-leaves  of  plants.     Good  examples  of  these  are  the 

dandelion,  chicory,  fall 
dandelion,  thistle,  hawk- 
weed,  pyrola,  plantain. 
How  are  the  leaves  of 
these  plants  kept  from 
shading  each  other? 

151.  Much-Divided 
Leaves. --Not  infre- 
quently leaves  are  cut 
into  slender  fringe  -  like 
divisions,  as  in  the  carrot, 
tansy,  southernwood, 
wormwood,  yarrow,  dog- 
fennel,  cypress-vine,  and  many  other  common  plants.  This 
kind  of  leaf  seems  to  be  adapted  to  offer  considerable 
surface  to  the  sun  without  cut- 
ting off  too  much  light  from 
other  leaves  underneath.  Such 
a  leaf  is  in  much  less  danger  of 
being  torn  by  severe  winds  than 
are  broader  ones  with  undivided 
margins.  The  same  purposes 
are  served  by  compound  leaves 
with  very  many  small  leaflets, 
such  as  those  of  the  honey- 
locust,  mimosa  acacia  (Fig.  113), 
and  other  trees  and  shrubs  of  the  pea  family.  What  kind 
of  shade  is  produced  by  a  horse-chestnut  or  a  maple  tree 
compared  with  that  of  a  honey-locust  or  an  acacia  ? 


FIG.  111.  —  Leaf -Mosaic  of  a 
Campanula. 


144  FOUNDATIONS  OF  BOTANY 

152.  Daily  Movements  of  Leaves.  —  Many  compound 
leaves  have  the  power  of  changing  the  position  of  their 
leaflets  to  accommodate  themselves  to  varying  conditions 
of  light  and  temperature.  Some  plants  have  the  power 
of  directing  the  leaves  or  leaflets  edgewise  towards  the 
sun  during  the  hottest  parts  of  the  day,  allowing  them  to 

extend  their  surfaces 
more  nearly  in  a  hori- 
zontal direction  during 
the  cooler  hours. 

The  so-called  " sleep" 
of  plants  has  long  been 
known,  but  this  subject 

FIG.  112.  —  A  Leaf  of  Red  Clover.  J 

At  the  left,  leaf  by  day  ;  at  the  right,  the  same      has    been   most   Caref  lllly 

leaf  asleep  at  night.  studied  rather  recently. 

The  wood  sorrel,  or  oxalis,  the  common  bean,  clovers, 
and  the  locust  tree  are  some  of  the  most  familiar  of 
the  plants  whose  leaves  assume  decidedly  different  posi- 
tions at  night  from  those  which  they  occupy  during  the 
day.  Sometimes  the  leaflets  rise  at  night,  and  in  many 
instances  they  droop,  as  in  the  red  clover  (Fig.  112)  and 
the  acacia  (Fig.  113).  One  useful  purpose,  at  any  rate, 
that  is  served  by  the  leaf's  taking  the  nocturnal  position  is 
protection  from  frost.  It  has  been  proved  experimentally 
that  when  part  of  the  leaves  on  a  plant  are  prevented  from 
assuming  the  folded  position,  while  others  are  allowed  to 
do  so,  and  the  plant  is  then  exposed  during  a  frosty  night, 
the  folded  ones  may  escape  while  the  others  are  killed. 
Since  many  plants  in  tropical  climates  fold  their  leaves 
at  night,  it  is  certain  that  this  movement  has  other  pur- 
poses than  protection  from  frost,  and  probably  there  is 


LEAF  EXPOSURE  TO  SUN  AND  AIR 


145 


much  yet  to  be  learned  about  the  meaning  and  importance 
of  leaf-movements. 

153.  Cause  of  Sleep-Movements.  --  The  student  may 
very  naturally  inquire  whether  the  change  to  the  noc- 
turnal position  is  brought  about  by  the  change  from  light 
to  darkness  or  whether  it  depends  rather  upon  the  time 
of  day.  It  will  be  interesting  to  try  an  experiment  in 
regard  to  this. 

EXPERIMENT   XXVI 

Remove  a  pot  containing  an  oxalis  from  a  sunny  window  to  a 
dark  closet,  at  about  the  same  temperature,  and  note  at  intervals  of 
five  minutes  the  condition  of  its  leaves  for  half  an  hour  or  more. 


FIG.  113.  — A  Leaf  of  Acacia. 
A,  as  seen  by  day  ;  /?,  the  same  leaf  asleep  at  night. 

154.    Structure  of  the  Parts  which  cause  Leaf -Motions.  - 
In  a  great  number  of  cases  the  daily  movements  of  leaves 
are  produced  by  special  organs  at  the  bases  of  the  leaf- 
stalks.    These    cushion-like    organs,   called  pulvini  (Fig. 
114),    are    composed   mainly    of    parenchymatous    tissue 


146 


FOUNDATIONS   OF  BOTANY 


(Sect.  106),  which  contains  much  water.  It  is  impossible 
fully  to  explain  in  simple  language  the  way  in  which  the 
cells  of  the  pulvini  act,  but  in  a  general  way  it  may  be 
said  that  changes  in  the  light  to  which  the  plant  is  exposed 
cause  rather  prompt  changes  in  the  amount  of  water  in 

the  cells    in    one   portion   or 
other  of  the  pulvinus.    If  the 
cells   on  one    side   are    filled 
fuller    of   water   than  usual, 
that  side  of  the  pulvinus  will 
be   expanded  and  make    the 
leaf-stalk    bend    toward    the 
opposite  side.     The  prompt- 
ness of  these 
movements  is  no 
doubt  in  consid- 
erable   measure 

FIG.  114.  — Compound  Leaf  of  Bean  with  '-^^Vil          due    to    the    fact 

Pulvinus.    (The  pulvinus  shows  as  an  Ij  ill            ,          .         ,              , 

enlargement,  in  the  figure  about  three-  I,  |         tnat  in    tne   pul- 

eighths  inch  long,  at  the  base  of  the  vini  (as  in  manV 

petiole.)  J 

other    parts    01 

plants)  the  protoplasm  of  adjacent  cells  is  connected. 
Delicate  threads  of  protoplasm  extend  through  the  cell- 
walls,  making  the  whole  tissue  a  living  web,  so  that  any 
suitable  stimulus  or  excitant  which  acts  on  one  part  of 
the  organ  will  soon  affect  the  whole  organ. 

155.  Vertically  Placed  Leaves.  —  Very  many  leaves,  like 
those  of  the  iris  (Fig.  44),  always  keep  their  principal  sur- 
faces nearly  vertical,  thus  receiving  the  morning  and  even- 
ing sun  upon  their  faces,  and  the  noonday  sun  (which  is 
so  intense  as  to  injure  them  when  received  full  on  the 


LEAF  EXPOSURE  TO  SUN  AND  AIR 


147 


surface)  upon  their  edges.  This  adjustment  is  most  per- 
fect in  the  compass-plant  of  the  prairies  of  the  Mississippi 
basin.  Its  leaves  stand  very  nearly  upright,  many  with 


A  B 

FIG.  115.— Leaves  standing  nearly  Vertical  in  Compass-Plant  (Silphium  laciniaturri). 
A,  view  from  east  or  west ;  B,  from  north  or  south. 

their  edges  just  about  north  and  south  (Fig.  115),  so  that 
the  rays  of  the  midsummer  sun  will,  during  every  bright 


148  FOUNDATIONS   OF   BOTANY 

day,  strike  the  leaf-surfaces  nearly  at  right  angles  during 
a  considerable  portion  of  the  forenoon  and  afternoon, 
while  at  midday  only  the  edge  of  each  leaf  is  exposed 
to  the  sun. 

156.  Movements  of  Leaves  and  Stems  toward  or  away 
from  Light  (Heliotropic  Movements).  —  The  student  doubt- 
less  learned  from  his  experiments  with  seedling  plants 
that  their  stems   tend  to  seek  light.      The  whole  plant 
above  ground  usually  bends  toward  the  quarter  from  which 
the  strongest  light  comes.      Such  movements  are   called 
heliotropie  from  two   Greek  words  which   mean  turning 
toward  the  sun.     How  do  the  plants  in  a  window  behave 
with  reference  to  the  light  ? 

EXPERIMENT   XXVII 

How  do  Young  Shoots  of  English  Ivy  bend  with  Reference  to  Light  ? 
—  Place  a  thrifty  potted  plant  of  English  ivy  before  a  small  window, 
e.g.,  an  ordinary  cellar  window,  or  in  a  large  covered  box,  painted  dull 
black  within  and  open  only  on  the  side  toward  a  south  window. 
After  some  weeks  note  the  position  of  the  tips  of  the  shoots. 
Explain  the  use  of  their  movements  to  the  plant. 

157.  Positive  and  Negative  Heliotropic  Movements ;  how 
produced.  —  Plants  may  bend  either  toward  or  away  from 
the  strongest  light.     In  the  former  case  they  are  said  to 
show  positive  heliotropism,  in  the  latter  negative  heliotro- 
pi&m.     In  both  cases  the  movement  is  produced  by  unequal 
growth,  brought  about  by  the  unequal  lighting  of  different 
sides  of  the  stem.     If  the  less  strongly  lighted  side  grows 
faster,  what  kind  of  heliotropism  results?     If  the  more 
strongly  lighted  side  grows  faster,  what  kind  of  heliotro- 
pism results  ?     How  would  a  plant  behave  if  placed  on  a 


LEAF  EXPOSURE  TO  SUN  AND  AIR       149 

revolving  table  before  a  window  and  slowly  turned  during 
the  hours  of  daylight? 

158,    Review  Summary  of  Chapter  X. 

f  For  vertical  twigs     .     .     . 
Leal  arrangement     ...      •<  _      .      .       1  ,  J . 

L  For  horizontal  twigs      .     .     . 

f  Apparatus  for 

Movements  of  leaves  .  .  -I  Causes  of 

[  Uses  of 

Compass-plants  .... 

(  Positive  . 


Heliotropic  bending  of  stems   ^  _ 

I  Negative . 


CHAPTER    XI 

MINUTE   STRUCTURE  OF  LEAVES;    FUNCTIONS  OF 
LEAVES 

159.  Leaf  of  Lily.  —  A  good  kind  of  leaf  with  which 
to  begin  the  study  of  the  microscopical  structure  of  leaves 
in  general  is  that  of  the  lily.1 

160.  Cross-Section  of  Lily  Leaf.  —  The  student  should  first  exam- 
ine  with  the  microscope  a  cross-section  of  the  leaf,  that  is,  a  very 
thin  slice,  taken  at  right  angles  to  the  upper  and  under  surfaces  and 
to  the  veins.     This  will  show  : 

(a)  The  upper  epidermis  of  the  leaf,  a  thin,  nearly  transparent 
membrane. 

(6)    The  intermediate  tissues. 

(c)    The  lower  epidermis. 

Use  a  power  of  from  100  to  200  diameters.  In  order  to  ascertain 
the  relations  of  the  parts,  and  to  get  their  names,  consult  Fig.  116. 
Your  section  is  by  no  means  exactly  like  the  figure  ;  sketch  it.  Label 
properly  all  the  parts  shown  in  your  sketch. 

Are  any  differences  noticeable  between  the  upper  and  the  lower 
epidermis?  Between  the  layers  of  cells  immediately  adjacent  to 
each? 

161.  Under  Surface  of  Lily  Leaf.  —  Examine  with  a  power  of  200 
or  more  diameters  the  outer  surface  of  a  piece  of  epidermis  from  the 
lower  side  of  the  leaf.2     Sketch   carefully,  comparing  your  sketch 
with  Figs.  117  and  118,  and  labeling  it  to  agree  with  those  figures. 

Examine  another  piece  from  the  upper  surface ;  sketch  it. 
How  does  the  number  of  stomata  in  the  two  cases  compare  ? 

1  Any  kind  of  lily  will  answer. 

2  The  epidermis  may  be  started  with  a  sharp  knife,  then  peeled  off  with 
small  forceps,  and  mounted  in  water  for  microscopical  examination. 

150 


MINUTE   STRUCTURE   OF  LEAVES 


151 


Take  measurements  from  the  last  three  sketches  with  a  scale  and, 
knowing  what  magnifying  power  was  used,  answer  these  questions  1  : 
(a)  How  thick  is  the  epidermis  ? 

(&)  What  is  the  length  and  the  breadth  of  the  epidermal  cells? 
(c)  What  is  the  average  size  of  the  pulp-cells  ? 

A  stoma  is  a  microscopic  pore  or  slit  in  the  epidermis. 
It  is  bounded  and  opened  and  shut  by  guard-cells  (Fig. 
118,  g),  usually  two  in  number.  These  are  generally 


FIG.  116.  —  Vertical  Section  of  the  Leaf  of  the  Beet.    (Much  magnified.) 

e,  epidermis  ;  p,  palisade-cells  (and  similar  elongated  cells) ;  r,  cells  filled  with 
red  cell  sap  ;  i,  intercellular  spaces ;  a,  air  spaces  communicating  with  the 
stomata ;  st,  stomata,  or  breathing  pores. 

1  The  teacher  may  measure  the  size  with  the  camera  lucida. 


152 


FOUNDATIONS  OF  BOTANY 


p.— 


A 


somewhat  kidney-shaped  and  become  more  or  less  curved 
as  they  are  fuller  or  less  full  of  water  (see  Sect.  170). 

162.  Calculation  of  Number  of  Stomata  per  Unit  of  Area. 
—  In  order  to  get  a  fairly  exact  idea  of  the  number  of 
stomata  on  a  unit  of  leaf-surface,  the  most  convenient 

plan  is  to  make 
use  of  a  photo- 
micrograph. The 
bromide  enlarge- 
ment No.  12  of 
the  Tower  series 
represents  about 
a  twenty-five- 
hundredth  of  a 
square  inch  of  the 
lower  epidermis  of 
the  cyclamen  leaf, 
magnified  until  it 
is  about  fifteen 
inches  square. 
Count  the  number 
of  stomata  on  the 
entire  photograph, 
then  calculate  the 
number  of  stomata 
on  a  square  inch 
of  the  surface  of 
this  leaf.  If  a  cyclamen  plant  has  twelve  leaves,  each 
with  an  average  area  of  six  square  inches,  calculate  the 
number  of  stomata  of  the  lower  epidermis  of  all  the  leaves 
taken  together. 


st 


•   PIG.  117.  —Epidermis  of  Leaf  of  Althaea. 

(Much  magnified.) 

A,  from  upper  surface ;  S,  from  lower  surface. 
h,  star-shaped  compound  hairs  ;  st,  stomata  ;  p, 
upper  ends  of  palisade-cells,  seen  through  the 
epidermis  ;  e,  cells  of  epidermis. 


MINUTE   STRUCTURE   OF  LEAVES 


153 


In  the  case  of  an  apple  tree,  where  the  epidermis  of  the 
lower  surface  of  the  leaf  contains  about  24,000  stomata  to 
the  square  inch,  or  the  black  walnut,  with  nearly  300,000 
to  the  square  inch, 
the  total  number 
on  a  tree  is  incon- 
ceivably large. 

163.  Uses  of  the 
Parts  examined.  — 
It  will  be  most  con- 
venient to  discuss 
the  uses  of  the 
parts  of  the  leaf  a 
little  later,  but  it 
will  make  matters 
simpler  to  state  at 
once  that  the  epi- 
dermis serves  as  a 
mechanical  protec- 
tion to  the  parts 
beneath  and  pre- 
vents excessive 
evaporation,  that 
the  palisade-cells 
(which  it  may  not  be  easy  to  make  out  very  clearly  in  a 
roughly  prepared  section)  hold  large  quantities  of  the  green 
coloring  matter  of  the  leaf  in  a  position  where  it  can 
receive  enough  but  no't  too  much  sunlight,  and  the  cells 
of  the  spongy  parenchyma  share  the  work  of  the  palisade- 
cells,  besides  evaporating  much  water.  The  stomata 
admit  air  to  the  interior  of  the  leaf  (where  the  air  spaces 


FIG.  118.  —A  Stoma  of  Thyme.    (Greatly  magnified.) 

A,  section  at  right  angles  to  surface  of  leaf  ;  S,  sur- 
face view  of  stoma.  cu,  cuticle  ;  g,  guard-cells  •, 
s,  stoma ;  e,  epidermal  cells ;  a,  air  chamber ; 
c,  cells  of  spongy  parenchyma  with  grains  of 
chlorophyll. 


154  FOUNDATIONS   OF  BOTANY 

serve  to  store  and  to  distribute  it),  they  allow  oxygen 
and  carbonic  acid  gas  to  escape,  and,  above  all,  they  regu- 
late the  evaporation  of  water  from  the  plant. 

164,  Leaf  of   "  India-Rubber   Plant."  l  —  Study  with   the  micro- 
scope, as  the  lily  leaf  was  studied,  make  the  same  set  of  sketches, 
note  the  differences  in  structure  between  the  two  leaves,  and  try  to 
discover  their  meaning. 

How  does  the  epidermis  of  the  two  leaves  compare  ? 

Which  has  the  larger  stomata? 

Which  would  better  withstand  great  heat  and  long  drought  ? 

165.  Chlorophyll  as   found  in  the  Leaf.  —  Slice  off  a 
little  of  the  epidermis  from  some  such  soft,  pulpy  leaf  as 


FIG.  119.  —  Section  through  Lower  Epidermis  of  Leaf  of  India-Rubber  Plant 

(Ficus  elastica).    (Magnified  330  diameters.) 

o,  opening  of  pit ;  p,  pit  leading  to  stoma ;  s,  stoma,  with  two  guard-cells  ;  w, 
water-storage  cells  of  epidermis  ;  a,  an  air  space ;  around  and  above  the  air 
spaces  are  cells  of  the  spongy  parenchyma. 

that  of  the  common  field  sorrel,2  live-for-ever,  or  spinach ; 
scrape  from  the  exposed  portion  a  very  little  of  the  green 
pulp  ;  examine  with  the  highest  power  attainable  with 
your  microscope,  and  sketch  several  cells. 

1  Ficus  elastica,  a  kind  of  fig  tree. 

2  Rumex  Acetosella. 


MINUTE   STRUCTURE   OF   LEAVES 


155 


Notice  that  the  green  coloring  matter  is  not  uniformly 
distributed,  but  that  it  is  collected  into  little  particles 
called  chlorophyll  bodies  (Fig.  120,  p). 

166.  Woody  Tissue  in  Leaves.  —  The  veins  of  leaves 
consist  of  nbro-vascular  bundles  containing  wood  and 
vessels  much  like  those  of  the  stem 
of  the  plant.  Indeed,  these  bundles 
in  the  leaf  are  continuous  with  those 
of  the  stem,  and  consist  merely  of 
portions  of  the  latter,  looking  f*-* 
as  if  unraveled,  which  pass  ; 
outward  and  upward  from  the 
stem  into  the  leaf  under 
the  name  of  leaf-traces. 
These  traverse  the  peti- 
ole often  in  a  somewhat 
irregular  fashion. 

EXPERIMENT   XXVIII 

Passage    of    Water     from 

v,  spirally  thickened  cells 
Stem    tO    Leaf. —Place    a      of  the  vein  ;  .p,  paren- 

freshly  cut  leafy  shoot  of  some     chyma-celis  of  the 

.  .  spongy  interior  of  the 

plant  with  large  thin  leaves,     leaf,  with  chlorophyll 

such  as  Hydrangea  hortensia,     Je°ndgies;  n'  nucleated 

in  eosin   solution   for  a  few 

minutes.     As  soon  as  the   leaves  show  a   decided  reddening,  pull 

some  of  them  off  and  sketch  the  red  stains  on  the  scars  thus  made. 

What  does  this  show? 

167,    Experimental  Study  of  Functions  of  Leaves.  —  The 

most  interesting  and  profitable  way  in  which  to  find  out 
what  work  leaves  do  for  the  plant  is  by  experimenting 
upon  them.  Much  that  relates  to  the  uses  of  leaves  is 


FIG.  120.  —  Termination 
of  a  Vein  in  a  Leaf. 
(Magnified  ahout  345 
diameters.) 


156  FOUNDATIONS   OF  BOTANY 

not  readily  shown  in  ordinary  class-room  experiments,  but 
some  things  can  readily  be  demonstrated  in  the  experi- 
ments which  follow. 

EXPERIMENT   XXIX 

Transpiration.  — Take  two  twigs  or  leafy  shoots  of  any  thin-leafed 
plant ; 1  cover  the  cut  end  of  each  stem  with  a  bit  of  grafting  wax  2 
to  prevent  evaporation  from  the  cut  surface.  Put  one  shoot  into  a 
fruit  jar,  screw  the  top  on,  and  leave  in  a  warm  room;  put  the  other 
beside  it,  and  allow  both  to  remain  some  hours.  Examine  the 
relative  appearance  of  the  two,  as  regards  wilting,  at  the  end  of  the 
time. 

Which  shoot  has  lost  most  ?  Why  ?  Has  the  one  in  the  fruit 
jar  lost  any  water  ?  To  answer  this  question,  put  the  jar  (without 
opening  it)  into  a  refrigerator ;  or,  if  the  weather  is  cold,  put  it  out 
of  doors  for  a  few  minutes,  and  examine  the  appearance  of  the  inside 
of  the  jar.  What  does  this  show  ?  3 

168.  Uses  of  the  Epidermis.4  —  The  epidermis,  by  its 
toughness,  tends  to  prevent  mechanical  injuries  to  the 
leaf,  and  after  the  filling  up  of  a  part  of  its  outer  por- 
tion with  a  corky  substance  it  greatly  diminishes  the  loss  of 
water  from  the  general  surface.  This  process  of  becom- 
ing filled  with  cork  substance,  suberin  (or  a  substance 
of  similar  properties  known  as  cutin)  is  essential  to  the 
safety  of  leaves  or  of  young  stems  which  have  to  with- 
stand heat  and  dryness.  The  corky  or  cutinized  cell- 
wall  is  waterproof,  while  ordinary  cellulose  allows  water 

1  Hydrangea,  squash,  melon,  or  cucumber  is  best;  many  other  kinds  will 
answer  very  well. 

2  Grafting  wax  may  be  bought  of  nurserymen  or  seedsmen. 

8  If  the  student  is  in  doubt  whether  the  jar  filled  with  ordinary  air  might 
not  behave  in  the  same  way,  the  question  may  be  readily  answered  by  putting 
a  sealed  jar  of  air  into  the  refrigerator. 

*  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  pp.  273-362. 


MINUTE   STRUCTURE    OF   LEAVES 


157 


to  soak  through  it  with  ease.  Merely  examining  sections 
of  the  various  kinds  of  epidermis  will  not  give  nearly 
as  good  an  idea  of  their  properties  as  can  be  obtained 
by  studying  the  behavior  during  severe  droughts  of 
plants  which  have  strongly  cutinized  surfaces  and  of 
those  which  have  not.  Fig.  121,  however,  may  convey 
some  notion  of  the  difference  between  the  two  kinds  of 
structure.  In  most 
cases,  as  in  the  india- 
rubber  tree,  the  ex- 
ternal epidermal  cells 
(and  often  two  or 
three  layers  of  cells 
beneath  these)  are 
filled  with  water,  and 
thus  serve  as  reser- 
voirs from  which  the 
outer  parts  of  the  leaf 
and  the  stem  are  at 
times  supplied. 

In  many  cases,  noticeably  in  the  cabbage,  the  epidermis 
is  covered  with  a  waxy  coating,  which  doubtless  increases 
the  power  of  the  leaf  to  retain  needed  moisture,  and 
which  certainly  prevents  rain  or  dew  from  covering  the 
leaf-surfaces,  especially  the  lower  surfaces,  so  as  to  hinder 
the  operation  of  the  stomata.  Many  common  plants,  like 
the  meadow  rue  and  the  nasturtium,  possess  this  power 
to  shed  water  to  such  a  degree  that  the  under  surface  of 
the  leaf  is  hardly  wet  at  all  when  immersed  in  water. 
The  air-bubbles  on  such  leaves  give  them  a  silvery 
appearance  when  held  under  water. 


FIG.  121.  —  Unequal  Development  of  Cuticle 

by  Epidermis-Cells. 

A,  epidermis  of  Butcher's  Broom  (Ruscus) ;  B, 
epidermis  of  sunflower ;  c,  cuticle ;  e,  epi- 
dermis-cells. 


158  FOUNDATIONS   OF  BOTANY 

169.  Hairs  on  Leaves.  —  Many  kinds  of  leaves  are  more 
or   less    hairy   or  downy,   as    those   of   the    mullein,   the 
"  mullein   pink,"   many    cinquefoils,   and    other    common 
plants.     In  some  instances  this  hairiness  may  be  a  protec- 
tion against  snails  or  other  small  leaf-eating  animals,  but 
in  other  cases  it  seems  to  be  pretty  clear  that  the  woolli- 
ness  (so  often  confined  to  the  under  surface)  is  to  lessen 
the  loss   of  water  through  the  stomata.     The  Labrador 
tea  is  an  excellent  example  of  a  plant,  with  a  densely 
woolly  coating  on  the  lower  surface  of  the  leaf.     The 
leaves,  too,  are  partly  rolled  up  (see  Fig.  224),  with  the 
upper  surface  outward,  so  as  to  give  the  lower  surface 
a  sort  of  deeply  grooved  form,  and  on  the  lower  surface 
all  of   the  stomata   are   placed.     This  plant,   like  some 
others  with  the  same  characteristics,  ranges  far  north  into 
regions    where    the    temperature,    even    during    summer, 
often  falls  so  low  that  absorption  of  water  by  the  roots 
ceases,  since  it  has  been  shown  that  this  nearly  stops  a 
little  above  the  freezing  point  of  water  (see  Exp.  XVII). 
Exposed  to  cold,  dry  winds,  the  plant  would  then  often 
be  killed  by  complete  drying  if  it  were  not  for  the  pro- 
tection afforded  by  the  woolly,  channeled  under  surfaces 
of  the  leaves.1 

170.  Operation  of  the  Stomata.  —  The  stomata  serve  to 
admit  air  to  the  interior  of  the  leaf,  and  to  allow  moisture, 
in  the  form  of  vapor,  to  pass  out  of  it.     They  do  this  not 
in  a  passive  way,  as  so  many  mere  holes  in  the  epidermis 
might,   but  to  a  considerable   extent  they   regulate  the 
rapidity  of  transpiration,   opening  more  widely  in  damp 
weather  and  closing   in    dry    weather.     The    opening  is 

1  This  adaptation  is  sufficiently  interesting  for  class  study. 


PLATE  IV.  —  A  Cypress  Swamp 


FUNCTIONS   OF   LEAVES  159 

caused  by  each  of  the  guard-cells  bending  into  a  more 
kidney-like  form  than  usual,  and  the  closing  by  a  straight- 
ening out  of  the  guard-cells.  The  under  side  of  the  leaf, 
free  from  palisade-cells,  abounding  in  intercellular  spaces, 
and  pretty  well  protected  from  becoming  covered  with 
rain  or  dew,  is  especially  adapted  for  the  working  of  the 
stomata,  and  accordingly  we  usually  find  them  in  much 
greater  numbers  on  the  lower  surface.  On  the  other 
hand,  the  little  flowerless  plants  known  as  liverworts, 
which  lie  prostrate  on  the  ground,  have  their  stomata  on 
the  upper  surface,  and  so  do  the  leaves  of  pond  lilies, 
which  lie  flat  on  the  water.  In  those  leaves  which  stand 
with  their  edges  nearly  vertical,  the  stomata  are  dis- 
tributed somewhat  equally  on  both  surfaces.  Stomata 
occur  in  the  epidermis  of  young  stems,  being  replaced 
later  by  the  lenticels.  Those  plants  which,  like  the 
cacti,  have  no  ordinary  leaves,  transpire  through  the 
stomata  scattered  over  their  general  surfaces. 

The  health  of  the  plant  depends  largely  on  the  proper 
working  condition  of  the  stomata,  and  one  reason  why 
plants  in  cities  often  fail  to  thrive  is  that  the  stomata 
become  choked  with  dust  and  soot.  In  some  plants,  as 
the  oleander,  provision  is  made  for  the  exclusion  of  dust 
by  a  fringe  of  hairs  about  the  opening  of  each  stoma.  If 
the  stomata  were  to  become  filled  with  water,  their  activ- 
ity would  cease  until  they  were  freed  from  it;  hence 
many  plants  have  their  leaves,  especially  the  under  sur- 
faces, protected  by  a  coating  of  wax  which  sheds  water. 

171.  Measurement  of  Transpiration.  —  We  have  already 
proved  that  water  is  lost  by  the  leaves,  but  it  is  worth 
while  to  perform  a  careful  experiment  to  reduce  our 


160 


FOUNDATIONS  OF  BOTANY 


knowledge  to  an  exact  form,  to  learn  how  much  water 
a  given  plant  transpires  under  certain  conditions.  It  is 
also  desirable  to  find  out  whether  different  kinds  of  plants 
transpire  alike,  and  what  changes  in  the  temperature,  the 
dampness  of  the  air,  the  brightness  of  the  light,  to  which 
a  plant  is  exposed,  have  to  do  with  its  transpiration. 
Another  experiment  will  show  whether  both  sides  of  a 
leaf  transpire  alike. 

EXPERIMENT   XXX 

Amount  of  Water  lost  by  Transpiration.  —  Procure  a  thrifty  hydran- 
gea1 and  a  small  "india-rubber  plant,"2  each  growing  in  a  small 

flower-pot,  and  with  the  number 
of  square  inches  of  leaf-surface 
in  the  two  plants  not  too  widely 
different.  Calculate  the  area  of 
the  leaf -surf  ace  for  each  plant, 
by  dividing  the  surface  of  a  piece 
of  tracing  cloth  into  a  series  of 
squares  one-half  inch  on  a  side, 
holding  an  average  leaf  of  each 
plant  against  this  and  counting 
the  number  of  squares  and  parts 
of  squares  covered  by  the  leaf. 
Or  weigh  a  square  inch  of  tinfoil 
on  a  very  delicate  balance,  cut 
out  a  piece  of  the  same  kind  of 
tinfoil  of  the  size  of  an  average 
leaf,  weigh  this  and  calculate  the 
leaf-area  from  the  two  weights. 
This  area,  multiplied  by  the'number  of  leaves  for  each  plant,  will 
give  approximately  the  total  evaporating  surface  for  each. 

Transfer  each  plant  to  a  glass  battery  jar  of  suitable  size.     Cover 


FIG.  122.  — A  Hydrangea  potted  in  a 
Battery  Jar  for  Exp.  XXX. 


1  The  common  species  of  the  greenhouses,  Hydrangea  Hortensia. 

2  This  is  really  a  fig,  Fieus  elastica. 


FUNCTIONS  OF  LEAVES  161 

the  jar  with  a  piece  of  sheet  lead,  slit  to  admit  the  stem  of  the  plant, 
invert  the  jar  and  seal  the  lead  to  the  glass  with  a  hot  mixture  of 
beeswax  and  rosin.  Seal  up  the  slit  and  the  opening  about  the 
stem  with  grafting  wax.  A  thistle-tube,  such  as  is  used  by  chem- 
ists, is  also  to  be  inserted,  as  shown  in  Fig.  122.1  The  mouth  of  this 
may  be  kept  corked  when  the  tube  is  not  in  use  for  watering. 

Water  each  plant  moderately  and  weigh  the  plants  separately  on 
a  balance  that  is  sensitive  to  one-fifth  gram.  Record  the  weights, 
allow  the  plants  to  stand  in  a  sunny,  warm  room  for  twenty-four^ 
hours  and  reweigh. 

Add  to  each  plant  just  the  amount  of  water  which  is  lost,2  and 
continue  the  experiment  in  the  same  manner  for  several  days  so  as 
to  ascertain,  if  possible,  the  effect  upon  transpiration  of  varying 
amounts  of  water  in  the  atmosphere. 

Calculate  the  average  loss  per  100  square  inches  of  leaf-surface  for 
each  plant  throughout  the  whole  course  of  the  experiment.  Divide 
the  greater  loss  by  the  lesser  to  find  their  ratio.  Find  the  ratio  of 
each  plant's  greatest  loss  per  day  to  its  least  loss  per  day,  and  by 
comparing  these  ratios  decide  which  transpires  more  regularly. 

Try  the  effect  of  supplying  very  little  water  to  each,  so  that  the 
hydrangea  will  begin  to  droop,  and  see  whether  this  changes  the 
relative  amount  of  transpiration  for  the  two  plants.  Vary  the  con- 
ditions of  the  experiment  for  a  day  or  two  as  regards  temperature, 
and  again  for  a  day  or  two  as  regards  light,  and  note  the  effect  upon 
the  amount  of  transpiration. 

The  structure  of  the  fig  (India-rubber  plant)  leaf  has  already  been 
studied.  That  of  the  hydrangea  is  looser  in  texture  and  more  like 
the  leaf  of  the  lily  or  the  beet  (Fig.  116). 

What  light  does  the  structure  throw  on  the  results  of  the  pre- 
ceding experiment  ? 

1  It  will  be  much  more  convenient  to  tie  the  hydrangea  if  one  has  been 
chosen  that  has  but  a  single  main  stem.    Instead  of  the  hydrangea,  the  com- 
mon cineraria,  Senecio  emeritus,  does  very  well. 

2  The  addition  of  known  amounts  of  water  may  be  made  most  conveniently 
by  measuring  it  in  a  cylindrical  graduate. 


162  FOUNDATIONS   OF  BOTANY 


EXPERIMENT   XXXI 

4fr 

Through  which  Side  of  a  Leaf  of  the  India-Rubber  Plant  does  Tran- 
spiration occur  ?  —  The  student  may  already  have  found  (Sect.  164) 
that  there  are  no  stomata  on  the  upper  surface  of  the  fig  leaf  which 
he  studied.  That  fact  makes  this  leaf  an  excellent  one  by  means  of 
which  to  study  the  relation  of  stomata  to  transpiration. 

Take  two  large,  sound  rubber-plant  leaves,  cut  off  pretty  close  to 
"the  stem  of  the  plant.  Slip  over  the  cut  end  of  the  petiole  of  each 
leaf  a  piece  of  small  rubber  tubing,  wire  this  on,  leaving  about  half 
of  it  free,  then  double  the  free  end  over  and  wire  tightly,  so  as  to 
make  the  covering  moisture-proof.  Warm  some  vaseline  or  grafting 
wax  until  it  is  almost  liquid,  arid  spread  a  thin  layer  of  it  smoothly 
over  the  upper  surface  of  one  leaf  and  the  lower  surface  of  the  other. 
Hang  both  up  in  a  sunny  place  in  the  laboi-atory  and  watch  them  for 
a  month  or  more. 

What  difference  in  the  appearance  of  the  two  leaves  becomes 
evident  ?  What  does  the  experiment  prove  ? 

172.  Endurance  of  Drought  by  Plants.  — Plants  in  a  wild 
state  have  to  live  under  extremely  different  conditions  as 
regards  water  supply  (see  Chapter  XXIV).  Observation 
of  growing  plants  during  a  long  drought  will  quickly 
show  how  differently  the  various  species  of  a  region  bear 
the  hardships  due  to  a  scanty  supply  of  moisture.  It  is 
still  easier,  however,  to  subject  some  plants  to  an  artificial 
drought  and  watch  their  condition. 

EXPERIMENT  XXXII 

Resistance  to  Drought.  —  Procure  at  least  one  plant  from  each  of 
these  groups  : 

Group  I.  Melon-cactus  (Echinocactus  or  Mamillarid),  prickly 
pear  cactus. 

Group  II.    Aloe,  Cotyledon  (often  called  Echeveria),  houseleek. 


FUNCTIONS   OF  LEAVES  163 

Group  III.  Live-for-ever  (Sedum  Telepkium),  Bryophyllum,  English 
ivy,  "  ivy-leafed  geranium,"  (Pelargonium  peltatum),  or  any  of  the 
fleshy-leafed  begonias. 

Group  IV.  Hydrangea  (//.  Hortensia),  squash  or  cucumber,  sun- 
flower. 

The  plants  should  be  growing  in  pots  and  well  rooted.  Water 
them  well  and  then  put  them  all  in  a  warm,  sunny  place.  Note  the 
appearance  of  all  the  plants  at  the  end  of  twenty-four  hours.  If  any 
are  wilting  badly,  water  them.  Keep  on  with  the  experiment,  in  no 
case  watering  any  plant  or  set  of  plants  until  it  has  wilted  a  good 
deal.  Record  the  observations  in  such  a  way  as  to  show  just  how 
long  a  time  it  took  each  plant  to  begin  to  wilt  from  the  time  when 
the  experiment  began.  If  any  hold  out  more  than  a  month,  they 
may  afterwards  be  examined  at  intervals  of  a  week,  to  save  the  time 
required  for  daily  observations.  If  possible,  account  by  the  struc- 
ture of  the  plants  for  some  of  the  differences  observed.  Try  to  learn 
the  native  country  of  each  plant  used  and  the  soil  or  exposure  natural 
to  it. 

173.  Course  traversed  by  Water  through  the  Leaf. — The 
same  plan  that  was  adopted  to  trace  the  course  of  water  in 
the  stem  (Exp.  XXI)  may  be  followed  to  discover  its  path 
through  the  leaf. 

EXPERIMENT  XXXIII 

Rise  of  Sap  in  Leaves.  —  Put  the  freshly  cut  ends  of  the  petioles 
of  several  thin  leaves  of  different  kinds  into  small  glasses,  each  con- 
taining eosin  solution  to  the  depth  of  one-quarter  inch  or  more. 
Allow  them  to  stand  for  half  an  hour,  and  examine  them  by  holding 
up  to  the  light  and  looking  through  them  to  see  into  what  parts  the 
eosin  solution  has  risen.  Allow  some  of  the  leaves  to  remain  as 
much  as  twelve  hours,  and  examine  them  again.  The  red-stained 
portions  of  the  leaf  mark  the  lines  along  which,  under  natural  con- 
ditions, sap  rises  into  it.  Cut  across  (near  the  petiole  or  midrib 
ends)  all  the  principal  veins  of  some  kind  of  large,  thin  leaf.  Then 
cut  off  the  petiole  and  at  once  stand  the  cut  end,  to  which  the  blade 


164  FOUNDATIONS  OF  BOTANY 

is  attached,  in  eosin  solution.     Repeat  with  another  leaf  and  stand 
in  water.     What  do  the  results  teach  ? 

174.  Total  Amount  of  Transpiration.  —  In  order  to  pre- 
vent wilting,  the  rise  of  sap  during  the  life  of  the  leaf 
must  have  kept  pace  with  the  evaporation  from  its  sur- 
face. The  total  amount  of  water  that  travels  through  the 
roots,  stems,  and  leaves  of  most  seed-plants  during  their 
lifetime  is  large,  relative  to  the  weight  of  the  plant  itself. 
During  173  days  of  growth  a  corn-plant  has  been  found  to 
give  off  nearly  31  pounds  of  water.  During  140  days  of 
growth  a  sunflower-plant  gave  off  about  145  pounds.  A 
.grass-plant  has  been  found  to  give  off  its  own  weight  of 
water  every  twenty-four  hours  in  hot,  dry  summer  weather. 
This  would  make  about  6  \  tons  per  acre  every  twenty-four 
hours  for  an  ordinary  grass-field,  or  rather  over  2200  pounds 
of  water  from  a  field  50  X 150  feet,  that  is,  not  larger  than 
a  good-sized  city  lot.  Calculations  based  on  observations 
made  by  the  Austrian  forest  experiment  stations  showed 
that  a  birch  tree  with  200,000  leaves,  standing  in  open 
ground,  transpired  on  hot  summer  days  from  700  to  900 
pounds,  while  at  other  times  the  amount  of  transpiration 
was  probably  not  more  than  18  to  20  pounds.1 

These  large  amounts  of  water  are  absorbed,  carried 
through  the  tissues  of  the  plant,  and  then  given  off  by  the 
leaves  because  the  plant-food  contained  in  the  soil-water 
is  in  a  condition  so  diluted  that  great  quantities  of  water 
must  be  taken  in  order  to  secure  enough  of  the  mineral 
and  other  substances  which  the  plant  demands  from  the 
soil.  Active  transpiration  may  also  have  other  causes. 

1  See  B.  E.  Fernow's  discussion  in  Report  of  Division  of  Forestry  of  U.  S. 
Department  of  Agriculture,  1889. 


FUNCTIONS   OF  LEAVES  165 

Meadow  hay  contains  about  two  per  cent  of  potash,  or 
2000  parts  in  100,000,  while  the  soil-water  of  a  good  soil 
does  not  contain  more  than  one-half  part  in  100,000  parts. 
It  would  therefore  take  4000  tons  of  such  water  to  furnish 
the  potash  for  one  ton  of  hay.  The  water  which  the 
root-hairs  take  up  must,  however,  contain  far  more  potash 
than  is  assumed  in  the  calculation  above  given,  so  that  the 
amount  of  water  actually  used  in  the  growth  of  a  ton  of 
hay  cannot  be  much  more  than  260  tons.1 

175.  Accumulation  of  Mineral  Matter  in  the  Leaf.  —  Just 
as  a  deposit  of  salt  is  found  in  the  bottom  of  a  seaside  pool 
of  salt  water  which  has  been  dried  up  by  the  sun,  so  old 
leaves  are  found  to  be  loaded  with  mineral  matter,  left 
behind  as  the  sap  drawn  up  from  the  roots  is  evaporated 
through  the  stomata.     A  bonfire  of  leaves  makes  a  sur- 
prisingly large  heap  of  ashes.     An  abundant  constituent 
of  the  ashes  of  burnt  leaves  is  silica,  a  substance  chemic- 
ally the  same  as  sand.     This  the  plant  is  forced  to  absorb 
along  with  the  potash,  compounds  of  phosphorus,  and  other 
useful  substances  contained  in  the  soil-water;  but  since 
the  silica  is  of  hardly  any  value  to  most  plants,  it  often 
accumulates  in  the  leaf  as  so  much  refuse.     Lime  is  much 
more  useful  to  the  plant  than  silica,  but  a  far  larger  quan- 
tity of  it  is  absorbed  than  is  needed;  hence  it,  too,  accu- 
mulates in  the  leaf. 

176.  Nutrition,  Metabolism.2  —  The  manufacture  of  the 
more  complex  plant-foods,  starch,  sugar,  and  so  on,  from 

1  See  the  article,  "  Water  as  a  Factor  in  the  Growth  of  Plants,"  by  B.  T. 
Galloway  and  Albert  F.  Woods,  Year-Book  of  U.  S.  Department  of  Agriculture, 
1894. 

2  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  pp.  371-483. 
Also  Pf offer's  Physiology  of  Plants,  translated  by  Ewart,  Chapter  VIII. 


166  FOUNDATIONS   OF  BOTANY 

the  raw  materials  which  are  afforded  by  the  earth  and  air 
and  all  the  steps  of  the  processes  by  which  these  foods  are 
used  in  the  life  and  growth  of  the  plant  are  together  known 
as  its  nutrition.  When  we  think  more  of  the  chemical 
side  of  nutrition  than  of  its  relation  to  plant-life,  we  call 
any  of  the  changes  or  all  of  them  metabolism,  which  means 
simply  chemical  transformation  in  living  tissues.  There 
are  two  main  classes  of  metabolism  —  the  constructive  kind, 
which  embraces  those  changes  which  build  up  more  com- 
plicated substances  out  of  simpler  ones  (Sect.  179),  and  the 
destructive  kind,  the  reverse  of  the  former  (Sect.  184).  A 
good  many  references  to  cases  of  plant  metabolism  have 
been  made  in  earlier  chapters,  but  the  subject  comes  up  in 
more  detail  in  connection  with  the  study  of  the  work  of  leaves 
than  anywhere  else,  because  the  feeding  which  the  ordinary 
seed-plant  does  is  very  largely  done  in  and  by  its  leaves. 

177.  Details  of  the  Work  of  the  Leaf.  —  A  leaf  has  four 
functions  to  perform:    (1)    Starch-making;    (2)    assimila- 
tion ; l  (3)  excretion  of  water  ;  (4)  respiration. 

178,  Absorption  of  Carbon  Dioxide  and  Removal  of  its 
Carbon.  —  Carbon  dioxide  is  a  constant  ingredient  of  the 
atmosphere,  usually  occurring  in  the  proportion  of  about 
four  parts  in  every  10,000  of  air  or  one  twenty-fifth  of  one 
per  cent.     It  is  a  colorless  gas,  a  compound  of  two  simple 
substances  or  elements,  carbon  and  oxygen,    the  former 
familiar  to  us  in  the  forms  of  charcoal  and  graphite,  the 
latter  occurring  as  the  active  constituent  of  air. 

1  In  many  works  on  Botany  (1)  and  (2)  are  both  compounded  under  the 
term  assimilation.  Many  botanists  (most  of  the  American  ones)  apply  the 
name  photosynthesis  or  photosyntax  to  the  starch-making  process,  but  these 
names  are  not  wholly  satisfactory,  and  perhaps  it  is  as  well  (as  suggested  by 
Professor  Atkinson)  to  name  the  process  from  its  result. 


FUNCTIONS   OF  LEAVES  167 

Carbon  dioxide  is  produced  in  immense  quantities  by 
the  decay  of  vegetable  and  animal  matter,  by  the  respira- 
tion of  animals,  and  by  all  fires  in  which  wood,  coal,  gas, 
or  petroleum  is  burned. 

Green  leaves  and  the  green  parts  of  plants,  when  they 
contain  a  suitable  amount  of  potassium  salts,  have  the 
power  of  removing  carbon  dioxide  from  the  air  (or  in 
the  case  of  some  aquatic  plants  from  water  in  which  it  is 
dissolved),  retaining  its  carbon  and  setting  free  part  or  all 
of  the  oxygen.  This  process  is  an  important  part  of  the 
work  done  by  the  plant  in  making  over  raw  materials  into 
food  from  which  it  forms  its  own  substance. 

EXPERIMENT   XXXIV 

Oxygen-Making  in  Sunlight.  —  Place  a  green  aquatic  plant  in  a 
glass  jar  full  of  ice-cold  fresh  water,  in  front  of  a  sunny  window.1 
Place  a  thermometer  in  the  jar,  watch  the  rise  of  temperature,  and 
note  at  what  point  you  first  observe  the  formation  of  oxygen -bub- 
bles. Remove  to  a  dark  closet  for  a  few  minutes  and  examine  by 
lamplight,  to  see  whether  the  rise  of  bubbles  still  continues. 

This  gas  may  be  shown  to  be  oxygen  by  collecting  some 
of  it  in  a  small  inverted  test-tube  filled  with  water  and 
thrusting  the  glowing  coal  of  a  match  just  blown  out  into 
the  gas.  It  is  not,  however,  very  easy  to  do  this  satisfac- 
torily before  the  class. 

Repeat  the  experiment,  using  water  which  has  been  well  boiled 
and  then  quickly  cooled.  Boiling  removes  all  the  dissolved  gases 
from  water,  and  they  are  not  re-dissolved  in  any  considerable  quantity 
for  many  hours. 

1  Elodea,  Myriophyllum,  Chrysosplenium,  Potamogeton,  Fontinalis,  any  of 
the  green  aquatic  flowering  plants,  or  even  the  common  confervaceous  plants, 
known  as  pond-scum  or  "  frog-spit,"  will  do  for  this  experiment. 


168  FOUNDATIONS   OF   BOTANY 

Ordinary  air,  containing  a  known  per  cent  of  carbon  dioxide, 
if  passed  very  slowly  over  the  foliage  of  a  plant  covered  with  a  bell- 
glass  and  placed  in  full  sunlight,  will,  if  tested  chemically,  on  com- 
ing out  of  the  bell-glass  be  found  to  have  lost  a  little  of  its  carbon 
dioxide.  The  pot  in  which  the  plant  grows  must  be  covered  with  a 
lid,  closely  sealed  on,  to  prevent  air  charged  with  carbon  dioxide  (as 
the  air  of  the  soil  is  apt  to  be)  from  rising  into  the  bell-glass. 

179.  Disposition  made  of  the  Absorbed  Carbon  Dioxide. 
-  It  would  lead  the  student  too  far  into  the  chemistry  of 
botany  to  ask  him  to  follow  out  in  detail  the  changes  by 
which  carbon  dioxide  lets  go  part  at  least  of  its  oxygen 
and  gives  its  remaining  portions,  namely,  the  carbon,  and 
perhaps  part  of  its  oxygen,  to  build  up  the  substance  of 
the  plant.  Starch  is  composed  of  three  elements  :  hydro- 
gen (a  colorless,  inflammable  gas,  the  lightest  of  known 
substances),  carbon,  and  oxygen.  Water  is  composed 
largely  of  hydrogen,  and,  therefore,  carbon  dioxide  and 
water  contain  all  the  elements  necessary  for  making  starch. 
The  chemist  cannot  put  these  elements  together  to  form 
starch,  but  the  plant  can  do  it,  and  at  suitable  temperatures 
starch-making  goes  on  constantly  in  the  green  parts  of 
plants  when  exposed  to  sunlight  and  supplied  with  water 
and  carbon  dioxide.1  The  seat  of  the  manufacture  is  in 
the  chlorophyll  bodies,  and  protoplasm  is  without  doubt  the 
manufacturer,  but  the  process  is  not  understood  by  chemists 
or  botanists.  No  carbon  dioxide  can  be  taken  up  and  used 
by  plants  growing  in  the  dark,  nor  in  an  atmosphere  con- 
taining only  carbon  dioxide,  even  in  the  light. 

1  Very  likely  the  plant  makes  sugar  first  of  all  and  then  rapidly  changes 
this  into  starch.  However  that  may  be,  the  first  kind  of  food  made  in  the 
leaf  and  retained  long  enough  to  be  found  there  by  ordinary  tests  is  starch. 
See  Pfeffer's  Physiology  of  Plants,  translated  by  Ewart,  Vol.  I,  pp.  317,  318. 


PLATE  V.  —  A  Saprophyte,  Indian  Pipe 


FUNCTIONS   OF  LEAVES  169 

A  very  good  comparison  of  the  leaf  to  a  mill  has  been 
made  as  follows  1 : 

The  mill :  Palisade-cells  and  underlying 

cells  of  the  leaf. 

Raw  material  used :  Carbon  dioxide,  water. 

Milling  apparatus  :  Chlorophyll  grains. 
Energy  by  which  the  mill 

is  run :  Sunlight. 

Manufactured  product :  Starch. 

Waste  product :  Oxygen. 

180.  Plants  Destitute  of  Chlorophyll  not  Starch-Makers. 
—  Aside  from  the  fact  that  newly  formed  starch  grains  are 

first  found  in  the  chlorophyll  bodies  of  the  leaf  and  the 
green  layer  of  the  bark,  one  of  the  best  evidences  of 
the  intimate  relation  of  chlorophyll  to  starch-making  is 
derived  from  the  fact  that  plants  which  contain  no  chloro- 
phyll cannot  make  starch  from  water  and  carbon  dioxide. 
Parasites,  like  the  dodder,  which  are  nearly  destitute  of 
green  coloring  matter,  cannot  do  this;  neither  can  sapro- 
phytes or  plants  which  live  on  decaying  or  fermenting 
organic  matter,  animal  or  vegetable.  Most  saprophytes, 
like  the  moulds,  toadstools,  and  yeast,  are  flowerless  plants 
of  low  organization,  but  there  are  a  few  (such  as  the 
Indian  pipe  (Plate  V),  which  flourishes  on  rotten  wood 
or  among  decaying  leaves)  that  bear  flowers  and  seeds. 

181.  Detection  of   Starch  in  Leaves.  —  Starch   may  be 
found  in  abundance  by  microscopical  examination  of  the 
green  parts   of  growing  leaves,   or  its  presence  may  be 
shown  by  testing  the  whole  leaf  with  iodine  solution. 

1  By  Professor  George  L.  Goodale. 


170 


FOUNDATIONS   OF  BOTANY 


EXPERIMENT   XXXV 

Occurrence  of  Starch  in  Nasturtium  Leaves.  —  Toward  the  close  of 
a  very  sunny  day  collect  some  bean  leaves  or  leaves  of  nasturtium 
(Tropceolum).  Boil  these  in  water  for  a  few  minutes,  to  kill  the 
protoplasmic  contents  of  the  cells  and  to  soften  and  swell  the  starch 
grains.1 

Soak  the  leaves,  after  boiling,  in  strong  alcohol  for  a  day  or  two, 
to  dissolve  out  the  chlorophyll,  which  would  otherwise  make  it  diffi- 
cult to  see  the  blue  color  of  the  starch  test,  if  any  were  obtained. 
Rinse  out  the  alcohol  with  plenty  of  water 
and  then  place  the  leaves  for  ten  or  fifteen 
minutes  in  a  solution  of  iodine,  rinse  off 
with  water  and  note  what  portions  of  the 
leaf,  if  any,  show  the  presence  of  starch. 

EXPERIMENT   XXXVI 

Consumption  of  Starch  in  Nasturtium 
(Tropmolum)  Leaves.  —  Select  some  healthy 
leaves  of  Tropseolum  on  a  plant  growing 
vigorously  indoors  or,  still  better,  in  the 
open  air.  Shut  off  the  sunlight  from 
parts  of  the  selected  leaves  (which  are  to 
be  left  on  the  plant  and  as  little  injured 
as  may  be)  by  pinning  circular  disks  of  cork  on  opposite  sides  of 
the  leaf,  as  shown  in  Fig.  123.  On  the  afternoon  of  the  next  day 
remove  these  leaves  from  the  plant  arid  treat  as  described  in  the 
preceding  experiment,  taking  especial  pains  to  get  rid  of  all  the 
chlorophyll  by  changing  the  alcohol  as  many  times  as  may  be  neces- 
sary. What  does  this  experiment  show  in  regard  to  the  consump- 
tion of  starch  in  the  leaf?  What  has  caused  its  disappearance? 

182.  Rate  at  which  Starch  is  manufactured. -- The 
amount  of  starch  made  in  a  day  by  any  given  area  of 

1  The  leaves,  collected  as  above  described,  may,  after  boiling,  be  kept  in 
alcohol  for  winter  use.  They  also  make  excellent  material  for  the  micro- 
scopical study  of  starch  in  the  leaf. 


FIG.  123.  — Leaf  of  Tropseo- 
lum partly  covered  with 
Disks  of  Cork  and  ex- 
posed to  Sunlight. 


FUNCTIONS   OF  LEAVES  171 

foliage  must  depend  on  the  kind  of  leaves,  the  tempera- 
ture of  the  air,  the  intensity  of  the  sunlight,  and  some 
other  circumstances.  Sunflower  leaves  and  pumpkin  or 
squash  leaves  have  been  found  to  manufacture  starch  at 
about  the  same  rate.  In  a  summer  day  fifteen  hours  long 
they  can  make  nearly  three-quarters  of  an  ounce  of  starch 
for  each  square  yard  of  leaf-surface.  A  full-grown  squash 
leaf  has  an  area  of  about  one  and  one-eighth  square  feet, 
and  a  plant  may  bear  as  many  as  100  leaves.  What  would 
be  the  daily  starch-making  capacity  of  such  a  plant  ? 1 

183.  Assimilation.  —  From  the  starch  in  the  leaf,  grape- 
sugar  or  malt-sugar  is  readily  formed,  and  some  of  this  in 
turn  is  apparently  combined  on  the  spot  with  nitrogen, 
sulphur,  and  phosphorus.  These  elements  are  derived 
from  nitrates,  sulphates,  and  phosphates,  taken  up  in  a 
dissolved  condition  by  the  roots  of  the  plant  and  trans- 
ported to  the  leaves.  The  details  of  the  process  are  not 
understood,  but  the  result  of  the  combination  of  the 
sugars  or  similar  substances  with  suitable  (very  minute) 
proportions  of  nitrogen,  sulphur,  and  phosphorus  is  to 
form  complex  nitrogen  compounds.  These  are  not  pre- 
cisely of  the  same  composition  as  the  living  protoplasm 
of  plant-cells  or  as  the  reserve  proteids  stored  in  seeds 
(Sects.  14,  17),  stems  (Sect.  127),  and  other  parts  of 
plants,  but  are  readily  changed  into  protoplasm  or  proteid 
foods  as  necessity  may  demand. 

Assimilation  is  by  no  means  confined  to  leaves  ;  indeed, 
most  of  it,  as  above  suggested,  must  take  place  in  other 
parts  of  the  plant.  For  instance,  the  manufacture  of  the 
immense  amounts  of  cellulose,  of  cork,  and  of  the  com- 

1  See  Pfeffer's  Physiology  of  Plants,  translated  by  Ewart,  Vol.  I,  p.  324. 


172  FOUNDATIONS   OF   BOTANY 

pound  (ligniri)  characteristic  of  wood-fiber,  that  go  to  make 
up  the  main  bulk  of  a  large  tree  must  be  carried  on  in  the 
roots,  trunk,  and  branches  of  the  tree. 

184.  Digestive  Metabolism.  —  Plant-food  in  order  to  be 
carried  to  the  parts  where  it  is  needed  must  be  dissolved, 
and  this  dissolving  often  involves  a  chemical  change  and 
is  somewhat  similar  to  digestion  as  it  occurs  in  animals. 
The  newly  made  starch  in  the  leaf  must  be  changed  to  a 
sugar  or  other  substance  soluble  in  water  before  it  can  be 
carried  to  the  parts  of  the  plant  where  it  is  to  be  stored 
or  to  rapidly  growing  parts  where  it  is  to  be  used  for 
building  material.     On  the  other  hand,  starch,  oil,  and 
such  insoluble  proteids  as  are  deposited  in  the  outer  por- 
tion of  the  kernel  of  wheat  and  other  grains  are  extremely 
well  adapted  to  serve  as  stored  food,  but  on  account  of 
their  insoluble  nature  are  quite  unfit  to  circulate  through 
the  tissues  of  the  plant.     The  various  kinds  of  sugar  are 
not  well  adapted  for  storage,  since  they  ferment  easily  in 
the  presence   of   warmth  and   moisture  if   yeast-cells  or 
suitable  kinds  of  bacteria  are  present. 

Two  important  differences  between  starch-making  in 
the  green  parts  of  plants  and  the  non-constructive  or  the 
destructive  type  of  metabolism  should  be  carefully  noticed. 
These  latter  kinds  of  metabolism  go  on  in  the  dark  as 
well  as  in  the  light  and  do  not  add  to  the  total  weight 
of  the  plant. 

185.  Excretion  of  Water  and  Respiration.  —  Enough  has 
been  said  in  Sect.  174  concerning  the  former  of  these  pro- 
cesses.    Respiration,  or  breathing  in  oxygen  and  giving 
off  carbonic  acid  gas,  is  an  operation  which  goes  on  con- 
stantly in  plants,  as  it  does  in  animals,  and  is  necessary  to 


FUNCTIONS   OF   LEAVES 


173 


their  life.  For,  like  animals,  plants  get  the  energy  with 
which  they  do  the  work  of  assimilation,  growth,  reproduc- 
tion, and  performing  their  movements  from  the  oxidation 
of  such  combustible  substances  as  oil,  starch,  and  sugar.1 

The  amount  of  oxy- 
gen absorbed  and  of  car- 
bonic acid  given  off  is, 
however,  so  trifling  com- 
pared with  the  amount 
of  each  gas  passing  in 
the  opposite  direction, 
while  starch-making  is 
going  on  in  sunlight, 
that  under  such  circum- 
stances it  is  difficult  to 
observe  the  occurrence 
of  respiration.  In  ordi- 

nary    leafy     plants     the      FIG.  124.  —  Cross-Section  of  Stem  of  Marestail 

&***»**  ** 


leaves  (through  their 
stomata)  are  the  principal  organs  for  absorption  of  air,  but 
much  air  passes  into  the  plant  through  the  lenticels  of 
the  bark. 

In  partly  submerged  aquatics  especial  provisions  are 
found  for  carrying  the  air  absorbed  by  the  leaves  down  to 
the  submerged  parts.  This  is  accomplished  in  pond  lilies 
by  ventilating  tubes  which  traverse  the  leaf-stalks  length- 
wise. In  many  cases  such  channels  run  up  and  down  the 
stem  (Fig.  124). 

1  The  necessity  of  an  air  supply  about  the  roots  of  the  plant  may  be  shown 
by  filling  the  pot  or  jar  in  which  the  hydrangea  was  grown  for  the  transpi- 
ration experiment  perfectly  full  of  water  and  noting  the  subsequent  appear- 
ance of  the  plant  at  periods  twelve  to  twenty-four  hours  apart. 


174 


FOUNDATIONS   OF   BOTANY 


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FUNCTIONS   OF  LEAVES  175 

187.  The  Fall  of  the  Leaf.  —  In  the  tropics  trees  retain 
most  of  their  leaves  the  year  round ;  a  leaf  occasionally 
falls,  but  no  considerable  portion  of  them  drops  at  any 
one  season.1  The  same  statement  holds  true  in  regard  to 
our  cone-bearing  evergreen  trees,  such  as  pines,  spruces, 
and  the  like.  But  the  impossibility  of  absorbing  soil- water 
when  the  ground  is  at  or  near  the  freezing  temperature 
(Exp.  XVII)  would  cause  the  death,  by  drying  up,  of 
trees  with  broad  leaf-surfaces  in  a  northern  winter.  And 
in  countries  where  there  is  much  snowfall,  most  broad- 
leafed  trees  could  not  escape  injury  to  their  branches  from 
overloading  with  snow,  except  by  encountering  winter 
storms  in  as  close-reefed  a  condition  as  possible.  For 
such  reasons  our  common  shrubs  and  forest  trees  (except 
the  cone-bearing,  narrow-leafed  ones  already  mentioned) 
are  mostly  deciduous,  that  is  they  shed  their  leaves  at  the 
approach  of  winter. 

The  fall  of  the  leaf  is  preceded  by  important  changes 
in  the  contents  of  its  cells. 

EXPERIMENT   XXXVII 

Does  the  Leaf  vary  in  its  Starch  Contents  at  Different  Seasons  ? 

Collect  in  early  summer  some  leaves  of  several  kinds  of  trees  and 
shrubs  and  preserve  them  in  alcohol.  Collect  others  as  they  are 
beginning  to  drop  from  the  trees  in  autumn  and  preserve  them  in 
the  same  way.  Test  some  of  each  lot  for  starch  as  described  in 
Sect.  181. 

What  does  the  result  indicate? 

Much  of  the  sugary  and  protoplasmic  contents  of  the 
leaf  disappears  before  it  falls.  These  valuable  materials 

1  Except  where  there  is  a  severe  dry  season. 


176  FOUNDATIONS   OF  BOTANY 

have  been  absorbed  by  the  branches  and  roots,  to  be  used 
again  the  following  spring. 

The  separation  of  the  leaf  from  the  twig  is  accomplished 
by  the  formation  of  a  layer  of  cork  cells  across  the  base  of 
the  petiole  in  such  a  way  that  the  latter  finally  breaks  off 
across  the  surface  of  the  layer.  A  waterproof  scar  is  thus 
already  formed  before  the  removal  of  the  leaf,  and  there  is 
no  waste  of  sap  dripping  from  the  wound  where  the  leaf- 
stalk has  been  removed,  and  no  chance  for  moulds  to 
attack  the  bark  or  wood  and  cause  it  to  decay.  In  com- 
pound leaves  each  leaflet  may  become  separated  from  the 
petiole,  as  is  notably  the  case  with  the  horse-chestnut  leaf 
(Fig.  102).  In  woody  monocotyledons,  such  as  palms,  the 
leaf-stalks  do  not  commonly  break  squarely  off  at  the  base, 
but  wither  and  leave  projecting  stumps  on  the  stem 
(Plate  VI). 

The  brilliant  coloration,  yellow,  scarlet,  deep  red,  and 
purple,  of  autumn  leaves  is  popularly  but  wrongly  sup- 
posed to  be  due  to  the  action  of  frost.  It  depends  merely 
on  the  changes  in  the  chlorophyll  grains  and  the  liquid 
cell-contents  that  accompany  the  withdrawal  of  the  proteid 
material  from  the  tissues  of  the  leaf.  The  chlorophyll 
turns  into  a  yellow  insoluble  substance  after  the  valuable 
materials  which  accompany  it  have  been  taken  away,  and 
the  cell  sap  at  the  same  time  may  turn  red.  Frost  per- 
haps hastens  the  break-up  of  the  chlorophyll,  but  individual 
trees  often  show  bright  colors  long  before  the  first  frost, 
and  in  very  warm  autumns  most  of  the  changes  in  the  foli- 
age may  come  about  before  there  has  been  any  frost. 

188.    Tabular  Review  of  Experiments. 
[Continue  the  table  from  Sect.  128.] 


PLATE  VI.  —  Fan  Palms 


FUNCTIONS  OF  LEAVES  177 

189.  Review  Summary  of  Minute  Structure  of  Leaves.1 

General  structure,  distribution  of 
parenchyma,  and  prosenchyma 

Layers  of  tissue  seen  on  a  cross- 
section  

Structure  of  epidermis      .     .     . 

Structure  of  stomata    .... 

Distribution  of  stomata    . 

Structure  and  distribution  of 
chlorophyll  bodies  .... 

190.  Review  Summary  of  Functions  of  Leaves. 

fibro-vascular  bundles 
epidermis  .... 
stomata      .... 
air  spaces  .... 
palisade-cells  . 
spongy  parenchyma 
waxy  coating .     .     . 
hairs 

f  from  the  air  .     .  •  . 
Substances  received  by  the  leaf  ....      I 

[  from  the  soil . 

Substances  manufactured  by  the  leaf  .     . 

,j; ,      , ,     ,     »  f  into  the  air 

Substances  given  off  by  the  leaf      ...      I 

\  into  the  stem       .     . 

Mineral  substances  accumulated  in  the  leaf 
Statistics  in  regard  to  transpiration     .     . 
Statistics  in  regard  to  starch-making  .     . 

1  Illustrate  with  sketches  and  diagrams. 


Principal  uses  of 


CHAPTER   XII 
PROTOPLASM    AND    ITS    PROPERTIES 

191.  The   Cell  in  its   Simplest  Form. — -Sufficient  has 
been  said  in  the  preceding  chapters,  and  enough  tissues 
have  been  microscopically  studied,  to  make  it  pretty  clear 
what  vegetable  cells,  as  they  occur  in  flowering  plants, 
are  like.     In  Chapter  XI,  leaf-cells  have  been  taken  for 
granted  and  their  work  described  in  some  detail.     Before 
going  further,  it  is  worth  while  to  consider  the  structure 
of  an  individual  cell,  and  to  see  of  what  kinds  of  activity 
it  is  capable. 

In  studying  the  minute  anatomy  of  bark,  wood,  pith, 
and  other  tissues  the  attention  is  often  directed  to  the 
cell-wall  without  much  regard  to  the  nature  of  the  cell- 
contents.  Yet  the  cell-wall  is  not  the  cell,  any  more  than 
the  lobster  shell  or  the  crayfish  shell  is  the  lobster  or  the 
crayfish.  The  contained  protoplasm  with  its  nucleus  is  the 
cell.1  The  cell  reduced  to  its  lowest  terms  need  not  have 
a  cell-wall,  but  may  consist  simply  of  a  mass  of  proto- 
plasm, usually  containing  a  portion  of  denser  consistency 
than  the  main  bulk,  known  as  the  nucleus. 

Such  cells,  without  a  cell-wall,  are  not  common  in  the  vege- 
table world,  but  are  frequently  encountered  among  animals. 

192,  The  Slime  Moulds.2  —  One  of  the  best  examples  of 
masses  of  naked  protoplasm  leading  an  individual  existence 

1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  pp.  21-51. 

2  Strasburger,  Noll,  Schenk,  and  Schimper's  Text-Book  of  Botany,  pp.  50-52 
and  302-305. 

178 


PROTOPLASM  AND  ITS  PROPERTIES       179 

is  found  in  the  slime  moulds,  which  live  upon  rotten  tan 
bark,  decaying  wood,  and  so  on.  These  curious  organ- 
isms have  so  many  of  the  characteristics  both  of  animals 
and  of  plants  that  they  have  been  described  in  zoologies 
under  the  former  title  and  in  botanies  under  the  latter 
one.  Perhaps  it  would  not  really  be  so  absurd  a  state- 
ment as  it  might  seem,  to  say  that  every  slime  mould  leads 
the  life  of  an  animal  during  one  period  of  its  existence  and 
of  a  plant  at  another  period.  At  any  rate,  whatever  their 
true  nature,  these  little  masses  of  unenclosed  protoplasm 
illustrate  admirably  some  of  the  most  important  properties 
of  protoplasm.  Slime  moulds  spring  from  minute  bodies 
called  spores  (Fig.  125,  a)  which  differ  from  the  seeds  of 
seed-plants  not  only  in  their  microscopic  size  but  still 
more  in  their  lack  of  an  embryo.  The  spores  of  slime 
moulds  are  capable,  when  kept  dry,  of  preserving  for 
many  years  their  power  of  germination,  but  in  the  pres- 
ence of  moisture  and  warmth  they  will  germinate  as  soon 
as  they  are  scattered.  During  the  process  of  germination 
t  tlje  spore  swells,  as  shown  at  6,  and  then  bursts,  discharging 
vvlts  protoplasmic  contents,  as  seen  at  c  and  d.  This  in  a 
A  few  minutes  lengthens  out  and  produces  at  one  end  a  hair- 
hike  cilium,  as  shown  at  e,  /,  g.  These  ciliated  bodies  are 
called  swarmspores,  from  their  power  of  swimming  freely 
about  by  the  vibrating  motion  of  the  cilia.  Every  swarm- 
spore  has  at  its  ciliated  end  a  nucleus,  and  at  the  other  end 
a  bubble-like  object  which  gradually  expands,  quickly  dis- 
appears, and  then  again  expands.  This  contractile  vacuole 
is  commonly  met  with  in  animalcules,  and  increases  the 
likeness  between  the  slime  moulds  and  many  microscopic 
animals.  The  next  change  of  the  swarmspores  is  into  an 


k 


180 


FOUNDATIONS   OF  BOTANY 


Amoeba  form  (so  called  from  one  of  the  most  interesting  and 
simplest  of  animals,  the  Amoeba,  found  on  the  surface  of 


FIG.  125.  —  A  Slime  Mould,    (a-m,  inclusive,  x  540  times,  n  x  90  times.) 

mud  and  the  leaves  of  water  plants).  In  this  condition, 
as  shown  at  A,  t,  &,  the  spores  creep  about  over  the  sur- 
face of  the  decaying  vegetable  material  on  which  the 


PROTOPLASM  AND  ITS  PROPERTIES        181 

slime  moulds  live.  Their  movement  is  caused  by  a  thrust- 
ing out  of  the  semi-liquid  protoplasm  on  one  side  of  the 
mass,  and  a  withdrawal  of  its  substance  from  the  other 
side.  At  length  many  amoeba-shaped  bodies  unite,  as  at  Z, 
to  form  a  larger  mass,  m,  which  finally  increases  to  the 
protoplasmic  network  shown  at  n.  This  eventually  col- 
lects into  a  roundish  or  egg-shaped  firm  body,  inside 
which  a  new  crop  of  spores  is  produced.  It  is  not  easy  to 
trace  the  manner  in  which  the  nourishment  of  these,  simple 
plants  is  taken.  Probably  they  absorb  it  from  the  decay- 
ing matter  upon  which  they  live  during  their  amoeba-like 
period,  and  after  they  have  formed  the  larger  masses,  n. 
193.  Characteristics  of  Living  Protoplasm.1  —  The  behav- 
ior of  the  slime  moulds  during  their  growth  and  transfor- 
mations, as  just  outlined,  affords  a  fair  idea  of  several  of 
the  remarkable  powers  which  belong  to  living  protoplasm, 
which  have  been  summed  up  as  follows : 

(1)  The  power  to  take  up  new  material  into  its  own 
substance  (selective  absorption}.     This  is  not  merely  a  proc- 
ess of  soaking  up  liquids,  such  as  occurs  when  dry  earth 
or  a  sponge  is  moistened.     The  protoplasmic  lining  of  a 
root-hair,  for  example,  selects  from  the  soil-water  some 
substances  and  rejects  others  (Sect.  65). 

(2)  The  ability  to  change  certain  substances  into  others 
of  different  chemical  composition  (metabolism,  Sect.  176). 
Carbon  dioxide  and  water,    losing  some   oxygen  in   the 
process,  are  combined  into  starch;  starch  is  changed  into 
various  kinds  of  sugar  and  these  back  into  starch  again ; 
starch  becomes  converted  into  vegetable  acids,  into  cellu- 
lose, or  into  oil ;  or  the  elements  of  starch  are  combined 

1  See  Huxley's  Essays,  Vol.  I,  essay  on  "  The  Physical  Basis  of  Life." 


182  FOUNDATIONS   OX   BOTANY 

with  nitrogen  to  m?.ke  various  proteid  compounds,  either 
for  immediate  use  or  for  reserve  food.  Many  other  com- 
plicated transformations  occur. 

(3)  The  power  to  cast  off   waste  or  used-up   material 
(excretion).     Getting  rid  of  surplus  water  (Sect.  174)  and 
of  oxygen  (Sect.  178)  constitutes  a  very  large  part  of  the 
excretory  work  of  plants. 

(4)  The  capacity  for  growth  and  the  production  of  off- 
spring (reproduction).     These  are  especially  characteristic 
of  living  protoplasm.     It  is  true  that  non-living  objects 
may  grow  in-  a  certain  sense,  as  an  icicle  or  a  crystal  of 
salt  or  of  alum  in  a  solution  of  its  own  material  does. 
But  growth  by  the  process  of  taking  suitable  particles 
into  the  interior  of  the  growing  substance  and  arranging 
them  into  an  orderly  structure  (Fig.  126)  is  possible  only 
in  the  case  of  live  protoplasm. 

(5)  The  possession  of  the  power  of  originating  move- 
ments  not  wholly  and  directly  caused  by  any  external 
impulse    (automatic  movements).     Such,   for  instance,  are 
the  lashing  movements  of  the  cilia  of  the  swarmspores 
of   slime   moulds,  or  the   slow  pendulum  movements  of 
Oscillatoria  (Sect.  269),  or  the  slow  vibrating  movements 
of  the   stipules  of   the  "  telegraplv   plant "  (Desmodium), 
not  uncommon  in  greenhouses.  ' 

(6)  The  power  of  shrinking  or  closing  up  (contractility). 
This  is  illustrated  by  the  action  of  the  contractile  vacuole 
of  the  slime  moulds  and  of  many  animalcules  and  by  all 
the  muscular  movements  of  animals. 

(7)  Sensitiveness  when  touched  or  otherwise  disturbed, 
for   instance,   by  a    change   of   light   or   of   temperature 
(irritability). 


PROTOPLASM  AND  ITS  PROPERTIES 


183 


194,    Nature  and  Occurrence  of  Irritability  in  Plants.1  - 
Mention  has  already  been  made  of  the  fact  that  certain 
parts  of  plants  respond  to  suitable  stimuli  that  is  exciting 


n 


FIG.  12fi.  —  Protoplasm  in  Ovule  and  Fruit  of  Snowberry  (Symphoricarpun 

racemosus). 
A,  cells  from  ovule,  x  340 ;  B,  cells  from  an  ovule  further  developed,  x  340 ;  (',  />, 

cells  from  pulp  of  fruit,  x  no ;  n,  nucleus  ;  p,  protoplasm  ;  s,  cell-sap. 
In  the  young  and  rapidly  growing  cells,  A  and  J5,  the  cell-sap  is  not  present,  or 

present  only  in  small  quantities,  while  in  the  older  cells,  C  and  D,  it  occupies 

a  large  portion  of  the  interior  of  the  cell. 

causes.      Geotropic    movements    (Sect.    70)    are    due    to 
the    response   of   roots  or  shoots  to   gravitation.     These 

1  See  Strasburger,  Noll,  Schenk,  and  Schimper's  Text-Book  of  Botany, 
Pp.  160-162  and  269-274. 


184 


FOUNDATIONS   OF   BOTANY 


movements  are  due  to  unequal  growth  induced  in  the 
younger  portions  of  the  plant  by  the  action  of  gravi- 
tation upon  it.  Other  movements  (of 
ordinary  foliage  leaves,  of  the  floral  leaves 
of  many  flowers,  and  of  other  parts  of  a 
few  flowers)  are  produced  by  changes  in 
the  distention  or  turgescence  of  some  of  the 
cells  in  the  organs  which  move  and  have 
nothing  to  do  with  growth.  The  closing 
of  the  leaves  of  insect-catching  plants  is 
briefly  described  in  Sect.  410,  and  the 
"sleep"  of  leaves,  due  to  movements  of 
the  pulvini,  was  described  in  Sect.  152. 
A  few  facts  in  regard  to  the  opening  and 
closing  of  flowers  will  be  found  in 
Sect.  440. 

The  stimuli  which  cause  movements  of 
leaves  or  of  the  irritable  parts  of  flowers 
are  of  several  kinds.  Light  is  the  main 
cause  which  induces  leaves  to  open  from 
their  night  position  to  that  usual  in  the 
daytime.  In  the  case  of  flowers,  it  is 
sometimes  light  and  sometimes  warmth 
FIG.  127.  —  stinging  which  causes  them  to  open.  Leaves  which 

Hair  of  Nettle,  with  .  ,  ,  11 

Nucleus.    (Much   catch  insects  may   be  made   to    close    by 
magnified.)  The  ar-   touching   them,  but   the   sensitive- plants, 

rows  show  the  direc- 
tion of  the  currents    of  which  there  are  several  kinds  found  in 

the  United  States,  and  a  much  more  sensi- 
tive one  in  tropical  America,  all  fold  their  leaflets,  on 
being  touched,  into  the  same  position  which  they  assume 
at  night. 


Lfl 


PROTOPLASM    AND    ITS   PROPERTIES  185 

195.  Circulation  of  Protoplasm.  —  When  confined  by  a 
cell-wall,  protoplasm  often  manifests  a  beautiful  and  con- 
stant rotating  movement,  traveling  incessantly  up  one 
side  of  the  cell  and  down  the  other.1  A  more  complicated 
motion  is  the  circulation  of  protoplasm,  shown  in  cells  of 
the  jointed  blue  hairs  in  the  flower  of  the  common  spider- 
wort  and  in  the  stinging  hairs  of  the  nettle  (Fig.  127). 
The  thin  cell- wall  of  each  hair  is  lined  with  a  protoplasmic 
layer  in  which  are  seen  many  irregular,  thread-like  cur- 
rents, marked  by  the  movements  of  the  granules,  of  which 
the  protoplasmic  layer  is  full. 
0 

1  See  Huxley  and  Martin's  Elementally  Biology,  under  Chara. 


CHAPTER    XIII 


INFLORESCENCE,    OR    ARRANGEMENT    OF    FLOWERS 
ON   THE    STEM 

196,  Regular  Positions  for  Flower-Buds.  —  Flower-buds, 
like  leaf -buds,  occur  regularly  either  in  the  axils  of  leaves 
or  at  the  end  of  the  stem  or  branch  and  are  therefore 
either  axillary  or  terminal. 

197,  Axillary    and    Solitary    Flowers;     Indeterminate 
Inflorescence.  —  The    simplest    possible    arrangement   for 

flowers  which  arise  from  the  axils  of 
leaves  is  to  have  a  single  flower  spring 
from  each  leaf-axil.  Fig.  128  shows 
how  this  plan  appears  in  a  plant  with 
opposite  leaves.  As  long  as  the  stem 
continues  to  grow,  the  production  of  new 
leaves  may  be  followed  by  that  of  new 


FIG.  128. —Axillary  and 
Solitary  FloAvers  of 
Pimpernel. 


FIG.  129.  —  Raceme    of 
Common  Red  Currant. 
p,  peduncle  ;  p',  pedicel ;  br,  bract. 


flowers.  Since  there  is  no  definite  limit  to  the  number 
of  flowers  which  may  appear  in  this  way,  the  mode  of 
flowering  just  described  (with  many  others  of  the  same 
general  character)  is  known  as  indeterminate  inflorescence. 

186 


ARRANGEMENT    OF    FLOWERS   ON   THE   STEM        187 


Fid.  130.  —  Simple  Umbel  of  Cherry. 


198.    The  Racemes  and  Related  Forms.  —  If  the  leaves 
along  the  stem  were  to  become  very  much  dwarfed  and  the 

flowers  brought  closer  together, 
as  they  frequently  are,  a  kind 
of  flower-cluster  like  that  of  the 
currant  (Fig.  129)  or  the  lily- 
of-the-valley  would  result.  Such 
an  inflorescence  is  called  a  ra- 
ceme ;  the  main  flower-stalk  is 
known  as  the  peduncle  ;  the  little 
individual  flower-stalks  are  pedi- 
cels, and  the  small,  more  or 
less  scale -like  leaves  of  the 
peduncle  are  bracts.1 
Frequently  the  lower  pedicels  of  a  cluster  on  the 
general  plan  of  the  raceme  are  longer  than  the  upper 
ones  and  make  a  some- 
what flat-topped  cluster, 
like  that  of  the  hawthorn, 
the  sheep  laurel,  or  the 
trumpet  creeper.  This 
is  called  a  corymb. 

In  many  cases,  for  ex- 
ample the  parsnip,  the 
Sweet  Cicely,  the  gin- 
seng, and  the  cherry,  a 
group  of  pedicels  of 
nearly  equal  length 


A  B 

FIG.  131.  — Catkins  of  Willow. 
A,  staminate  flowers  ;  fi,  pistillate  flowers 


1  It  is  hardly  necessary  to  say  that  the  teacher  will  find  it  better  in  every 
way,  if  material  is  abundant,  to  begin  the  study  of  flower-clusters  with  the 
examination  of  typical  specimens  by  the  class. 


188 


FOUNDATIONS   OF   BOTANY 


spring    from   about   the    same    point.      This    produces    a 
flower-cluster  called  the  umbel  (Fig.  130). 

199.    Sessile  Flowers  and  Flower-Clusters Often  the 

pedicels  are  wanting,  or  the  flowers  are  sessile,  and  then 
a  modification  of  the  raceme  is  produced  which  is  called 
a  spike,  like  that  of  the  plantain  (Fig.  132).  The 
willow,  alder,  birch,  poplar,  arid  many  other  c'ommon 
trees  bear  a  short,  flexible,  rather  scaly  spike  (Fig. 
131),  which  is  called  a  catkin. 

The  peduncle  of  a  spike  is  often  so  much  short- 
ened as  to  bring  the  flowers  into  a  somewhat  globu- 
lar mass.     This  is  called  a  head  (Fig.  132).    Around 
the  base   of  the  head  usually 
occurs  a  circle  of  bracts  known 
as   the    involucre.      The    same 
name  is  given  to  a  set  of  bracts 
which  often  surround  the  bases 
of  the  pedicels  in  an  umbel. 

200.  The  Composite  Head.  — 
The  plants  of  one  large  group, 
of  which  the  dandelion,  the 
daisy,  the  thistle,  and  the  sun- 
flower are  well-known  members,  bear  their  flowers  in 
close  involucrate  heads  on  a  common  receptacle.  The 
whole  cluster  looks  so  much  like  a  single  flower  that  it  is 
usually  taken  for  one  by  non-botanical  people.  In  many 
of  the  largest  and  most  showy  heads,  like  that  of  the 
sunflower  and  the  daisy,  there  are  two  kinds  of  flowers, 
the  ray-flowers,  around  the  margin,  and  the  tubular  disk- 
flowers  of  the  interior  of  the  head  (Fig.  133).  The  early 
botanists  supposed  the  whole  flower-cluster  to  be  a  single 


FIG.  132.  —  Spike  of  Plantain  and 
Head  of  Red  Clover. 


ARRANGEMENT   OF   FLOWERS   ON  THE    STEM        189 


FIG.  133.  — Head  of  Yarrow. 

A,  top  view.  (Magnified.)  B.,  lengthwise  section.  (Magnified.)  re,  receptacle  ;  i, 
involucre  ;  r,  ray-flowers  ;  rf,  disk-flowers  ;  c,  corolla  ;  s,  stigma  ;  ch,  chaff , 
or  bracts  of  receptacle. 


FIG. 134. 
Panicle  of  Oat. 


FIG.  135.  —Compound  Umbel 
of  Carrot. 


190 


FOUNDATIONS    OF   BOTANY 


compound  flower.  This  belief  gave  rise  to  the  name  of 
one  family  of  plants,  Compositce,  that  is,  plants  with  com- 
pound flowers.  In  such  heads  as  those  of  the  thistle,  the 
cud  weed,  and  the  everlasting  there  are  no  ray-flowers, 
and  in  others,  like  those  of  the  dandelion  and  the  chicory, 
all  the  flowers  are  ray-flowers. 

201.    Compound  Flower-Clusters.  —  If  the  pedicels  of  a 
raceme  branch,  they  may  produce  a  compound  raceme,  or 


\ 


p 


/ 


A  BCD 

FIG.  136.  —  Diagrams  of  Inflorescence. 
A,  panicle  ;  B,  raceme  ;  C,  spike  ;   E ,  umbel ;  D,  head. 

panicle,  like  that  of  the  oat  (Fig.  134).1  Other  forms  of 
compound  racemes  have  received  other  names. 

An  umbel  may  become  compound  by  the  branching  of 
its  flower-stalks  (Fig.  135),  each  of  which  then  bears  a 
little  umbel,  an  umbellet. 

202.  Inflorescence  Diagrams.  —  The  plan  of  inflorescence 
may  readily  be  indicated  by  diagrams  like  those  of  Fig.  136. 

The  student  should  construct  such  diagrams  for  some  rather  com- 
plicated flower-clusters,  like  those  of  the  grape,  horse-chestnut  or 
buckeye,  hardhack,  vervain,  or  many  grasses. 

1  Panicles  may  also  be  formed  by  compound  cymes  (see  Sect.  204). 


ARRANGEMENT    OF    FLOWERS    ON    THE    STEM        191 


203.  Terminal    Flowers ;    Determinate   Inflorescence.  — 

The  terminal  bud  of  a  stem  may  be  a  flower-bud. '  In  this 
case  the  direct  growth  of  the  stem  is  stopped  or  deter- 
mined by  the  appearance  of  the  flower ;  hence  such  plants 
are  said  to  have  a  determinate  inflorescence.  The  simplest 
possible  case  of  this  kind  is  that 
in  which  the  stem  bears  but  one 
flower  at  its  summit. 

204.  The  Cyme.  — Very  often 
flowers  appear  from  lateral  (axil- 
lary) buds,  below  the  terminal 
flower,  and  thus  give  rise  to  a 
flower-cluster  called  a  cyme. 
This  may  have  only  three  flowers, 
and  in  that  case  would  look  very 
much  like   a   three-flowered 
umbel.      But   in    the    raceme, 
corymb,  and  umbel  the  order  of 
flowering  is  from  below  upward, 
or  from  the  outside  of  the  clus- 
ter inward,  because  the  lowest  or  the  outermost  flowers 
are  the  oldest,  while  in  determinate  forms  of  inflorescence 
the  central  flower  is  the  oldest,  and  therefore  the  order  of 
blossoming  is  from  the  center  outwards.     Cymes  are  very 
commonly  compound'  like  those  of  the  elder  and  of  many 
plants  of  the  pink  family,  such  as  the  Sweet  William  and 
the  mouse-ear  chick  weed  (Fig.  137).     They  may  also,  as 
already  mentioned,  be    panicled,  thus    making    a  cluster 
much  like  Fig.  136,  A. 


FIG.  137.  —  Compound  Cyme  of 

Mouse-Ear  Chickweed. 
t,  the  terminal  (oldest)  flower. 


CHAPTER    XIV 
THE    STUDY    OF   TYPICAL   FLOWERS 

(Only  one  of  the  three  flowers  described  to  be  studied  by  aid  of  these 
directions.) 

205.  The  Flower  of  the  Trillium.  —  Cut  off  the  flower-stalk  rather 
close  to  the  flower;  stand  the  latter,  face  down,  on  the  table,  and 
draw  the  parts  then  shown.  Label  the  green  leaf-like  parts  sepals, 
and  the  white  parts,  which  alternate  with  these,  petals.  Turn  the 
flower  face  up,  and  make  another  sketch,  labeling  the  parts  as  before, 
together  with  the  yellow  enlarged  extremities  or  anthers  of  the  stalked 
organs  called  stamens. 

Note  and  describe  the  way  in  which  the  petals  alternate  with  the 
sepals.  Observe  the  arrangement  of  the  edges  of  the  petals  toward 
the  base,  — how  many  with  both  edges  outside  the  others,  how  many 
with  both  edges  inside,  how  many  with  one  edge  in  and  one  out. 

Note  the  veining  of  both  sepals  and  petals,  more  distinct  in 
which  set?1 

Pull  off  a  sepal  and  make  a  sketch  of  it,  natural  size  ;  then  remove 
a  petal,  flatten  it  out,  and  sketch  it,  natural  size. 

Observe  that  the  flower-stalk  is  enlarged  slightly  at  the  upper  end 
into  a  rounded  portion,  the  receptacle,  on  which  all  the  parts  of  the 
flower  rest. 

Note  how  the  six  stamens  arise  from  the  receptacle  and  their 
relations  to  the  origins  of  the  petals.  Remove  the  remaining  petals 

1  In  flowers  with  delicate  white  petals  the  distribution  of  the  fibro-vascular 
bundles  in  these  can  usually  be  readily  shown  by  standing  the  freshly  cut  end 
of  the  peduncle  in  red  ink  for  a  short  time,  until  colored  veins  begin  to  appear 
in  the  petals.  The  experiment  succeeds  readily  with  apple,  cherry,  or  plum 
blossoms ;  with  white  gilliflower  the  coloration  is  very  prompt.  Lily-of-the- 
valley  is  perhaps  as  interesting  a  flower  as  any  on  which  to  try  the  experi- 
ment, since  the  well-defined  stained  stripes  are  separated  by  portions  quite 
free  from  stain,  and  the  pistils  are  also  colored. 

192 


THE   STUDY   OF  TYPICAL   FLOWERS  193 

(cutting  them  off  near  the  bottom  with  a  knife),  and  sketch  the  sta- 
mens, together  with  the  other  object,  the  pistil,  which  stands  in  the 
center. 

Cut  off  one  stamen,  and  sketch  it  as  seen  through  the  magnifying 
glass.  Notice  that  it  consists  of  a  greenish  stalk,  the  filament,  and 
a  broader  portion,  the  anther  (Fig.  149).  The  latter  is  easily  seen 
to  contain  a  prolongation  of  the  green  filament,  nearly  surrounded 
by  a  yellow  substance.  In  the  bud  it  will  be  found  that  the  anther 
consists  of  two  long  pouches  or  anther-cells,  which  are  attached  by 
their  whole  length  to  the  filament,  and  face  inward  (towards  the 
center  of  the  flower).  When  the  flower  is  fairly-  open,  the  anther- 
cells  have  already  split  down  their  margins,  and  are  discharging  a 
yellow,  somewrhat  sticky  powder,  the  pollen. 

Examine  one  of  the  anthers  with  the  microscope,  using  the  two- 
inch  objective,  and  sketch  it. 

Cut  away  all  the  stairens,  and  sketch  the  pistil.  It  consists  of  a 
stout  lower  portion,  the  ovary,  which  is  six-ridged  or  angled,  and 
which  bears  at  its  summit  three  slender  stigmas. 

In  another  flower,  which  has  begun  to  wither  (and  in  which  the 
ovary  is  larger  than  in  a  newly  opened  flower),  cut  the  ovary  across 
about  the  middle,  and  try  to  make  out  with  the  magnifying  glass 
the  number  of  chambers  or  cells  which  it  contains.  Examine  the 
cross-section  with  the  two-inch  objective ;  sketch  it,  and  note  partic- 
ularly the  appearance  and  mode  of  attachment  of  the  undeveloped 
seeds  or  ovules  with  which  it  is  filled.  Make  a  vertical  section  of 
another  rather  mature  ovary,  and  examine  this  in  the  same  way. 

Using  a  fresh  flower,  construct  a  diagram  to  show  the  relation  of 
the  parts  on  an  imaginary  cross-section,  as  illustrated  in  Fig.  157.1 
Construct  a  diagram  of  a  longitudinal  section  of  the  flower,  on  the 
general  plan  of  those  in  Fig.  155,  but  showing  the  contents  of  the 
ovary. 

Make  a  tabular  list  of  the  parts  of  the  flower,  beginning  with  the 
sepals,  giving  the  order  of  parts  and  number  in  each  set. 

1  It  is  important  to  notice  that  such  a  diagram  is  iiot  a  picture  of  the  section 
actually  produced  by  cutting  through  the  flower  crosswise  at  anyone  level, 
but  that  it  is  rather  a  projection  of  the  sections  through  the  most  typical  part 
of  each  of  the  floral  organs. 


194  FOUNDATIONS   OF    BOTANY 

206,  The  Flower  of  the  Tulip.1  —  Make  a  diagram  of  a  side  view 
of  the  well-opened  flower,  as  it  appears  when  standing  in  sunlight. 
Observe  that  there  is  a  set  of  outer  flower-leaves  and  a  set  of  inner 
ones.2  Label  the  outer  set  sepals  and  the  inner  set  petals.  In  most 
flowers  the  parts  of  the  outer  set  are  greenish,  and  those  of  the  inner 
set  of  some  other  color.  It  is  often  convenient  to  use  the  name 
perianth,  meaning  around  the  flower,  for  the  two  sets  taken  together. 
Note  the  white  waxy  bloom  on  the  outer  surface  of  the  outer  seg- 
ments of  the  perianth.  What  is  the  use  of  this  ?  Note  the  manner 
in  which  the  inner  segments  of  the  perianth  arise  from  the  top  of  the 
peduncle  and  their  relation  to  the  points  of  attachment  of  the  outer 
segments.  In  a  flower  not  too  widely  opened,  note  the  relative  posi- 
tion of  the  inner  segments  of  the  perianth,  how  many  wholly  outside 
the  other  two,  how  many  wholly  inside,  how  many  with  one  edge  in 
and  one  edge  out. 

Remove  one  of  the  sepals  by  cutting  it  off  close  to 'its  attachment 
to  the  peduncle,  and  examine  the  veining  by  holding  it  up  in  a  strong 
light  and  looking  through  it.  Make  a  sketch  to  show  the  general 
outline  and  the  shape  of  the  tip. 

Examine  a  petal  in  the  same  way,  and  sketch  it. 

Cut  off  the  remaining  portions  of  the  perianth,  leaving  about  a 
quarter  of  an  inch  at  the  base  of  each  segment.  Sketch  the  upright, 
triangular,  pillar-like  object  in  the  center,  label  it  pistil,  sketch  the 
organs  which  spring  from  around  its  base,  and  label  these  stamens. 

Note  the  fact  that  each  stamen  arises  from  a  point  just  above  and 
within  the  base  of  a  segment  of  the  perianth.  Each  stamen  consists 
of  a  somewhat  conical  or  awl-shaped  portion  below,  the  filament,  sur- 
mounted by  an  ovate  linear  portion,  the  anther.  Sketch  one  of  the 
stamens  about  twice  natural  size  and  label  it  x  2.  Is  the  attach- 
ment of  the  anther  to  the  filament  such  as  to  admit  of  any  nodding 
or  twisting  movement  of  the  former  ?  In  a  young  flower,  note  the 
two  tubular  pouches  or  anther-cells  of  which  the  anther  is  composed, 
and  the  slits  by  which  these  open.  Observe  the  dark-colored  pollen 

1  Tulipa  Gesneriana.    As  the  flowers  are  rather  expensive,  and  their  parts 
are  large  and  firm,  it  is  not  absolutely  necessary  to  give  a  flower  to  each  pupil, 
but  some  may  be  kept  entire  for  sketching  and  others  dissected  by  the  class. 
All  the  flowers  must  be  single. 

2  Best  seen  in  a  flower  which  is  just  opening. 


THE    STUDY    OF    TYPICAL    KLOVVKRS  195 

which  escapes  from  the  anther-cells  and  adheres  to  paper  or  to  the 
fingers.  Examine  a  newly  opened  anther  with  the  microscope,  using 
the  two-inch  objective,  and  sketch  it. 

Cut  away  all  the  stamens  and  note  the  two  portions  of  the  pistil, 
a  triangular  prism,  the  ovary,  and  three  roughened  scroll-like  objects 
at  the  top,  the  three  lobes  of  the  stigma.  Make  a  sketch  of  these 
parts  about  twice  natural  size,  and  label  them  x  2.  Touch  a  small 
earners-hair  pencil  to  one  of  the  anthers,  and  then  transfer  the  pollen 
thus  removed  to  the  stigma.  This  operation  is  merely  an  imitation 
of  the  work  done  by  insects  which  visit  the  flowers  out  of  doors. 
Does  the  pollen  cling  readily  to  the  rough  stigmatic  surface  ?  Examine 
this  adhering  pollen  with  the  two-inch  objective,  and  sketch  a  few 
grains  of  it,  together  with  the  bit  of  the  stigma  to  which  it  clings. 
Compare  this  drawing  with  Fig.  162.  Make  a  cross-section  of  the 
ovary  about  midway  of  its  length,  and  sketch  the  section  as  seen 
through  the  magnifying  glass.  Label  the  three  chambers  shown 
cells  of  the  ovary  l  or  locules,  and  the  white  egg-shaped  objects  within 
ovules.2 

Make  a  longitudinal  section  of  another  ovary,  taking  pains  to 
secure  a  good  view  of  the  ovules,  and  sketch  as  seen  through  the 
magnifying  glass. 

Making  use  of  the  information  already  gained  and  the  cross- 
section  of  the  ovary  as  sketched,  construct  a  diagram  of  a  cross- 
section  of  the  entire  flower  on  the  same  general  plan  as  those  shown 
in  Fig.  157.3 

Split  a  flower  lengthwise,4  and  construct  a  longitudinal  section  of 
the  entire  flower  on  the  plan  of  those  shown  in  Fig.  155,  but  showing 
the  contents  of  the  ovary. 

207.  The  Flower  of  the  Buttercup.  —  Make  a  diagram  of  the 
mature  flower  as  seen  in  a  side  view,  looking  a  little  down  into  it. 
Label  the  pale  greenish-yellow,  hairy,  outermost  parts  sepals,  and 

1  Notice  that  the  word  cell  here  means  a  comparatively  large  cavity,  and  is 
not  used  in  the  same  sense  in  which  we  speak  of  a  wood-cell  or  a  pith-cell. 

2  The  section  will  be  more  satisfactory  if  made  from  an  older  flower,  grown 
out  of  doors,  from  which  the  perianth  has  fallen.     In  this  case  label  the  con- 
tained objects  seeds. 

8  Consult  also  the  footnote  on  p.  193. 

4  One  will  do  for  an  entire  division  of  the  class. 


196  FOUNDATIONS   OF   BOTANY 

the  larger  bright  yellow  parts  above  and  within  these  petals,  and 
the  yellow-knobbed  parts  which  occupy  a  good  deal  of  the  interior 
of  the  flower  stamens. 

Note  the  difference  in  the  position  of  the  sepals  of  a  newly 
opened  flower  and  that  of  the  sepals  of  a  flower  which  has  opened  as 
widely  as  possible.  Note  the  way  in  which  the  petals  are  arranged 
in  relation  to  the  sepals.  Jn  an  opening  flower  observe  the  arrange- 
ment of  the  edges  of  the  petals,  how  many  entirely  outside  the 
others,  how  many  entirely  inside,  how  many  with  one  edge  in  and 
the  other  out. 

Cut  off  a  sepal  and  a  petal,  each  close  to  its  attachment  to  the 
flower ;  place  both,  face  down,  on  a  sheet  of  paper,  and  sketch  about 
twice  the  natural  size  and  label  it  x  2.  Describe  the  difference  in 
appearance  between  the  outer  and  the  inner  surface  of  the  sepal  and 
of  the  petal.  Note  the  little  scale  at  the  base  of  the  petal,  inside. 

Strip  off  all  the  parts  from  a  flower  which  has  lost  its  petals, 
until  nothing  is  left  but  a  slender  conical  object  a  little  more  than 
an  eighth  of  an  inch  in  length.  This  is  the  receptacle  or  summit  of 
the  peduncle. 

In  a  fully  opened  flower,  note  the  numerous  yellow-tipped  stamens, 
each  consisting  of  a  short  stalk,  the  filament,  and  an  enlarged  yellow 
knob  at  the  end,  the  anther.  Note  the  division  of  the  anther  into 
two  portions,  which  appear  from  the  outside  as  parallel  ridges,  but 
which  are  really  closed  tubes,  the  anther-cells. 

Observe  in  the  interior  of  the  flower  the  somewhat  globular  mass 
(in  a  young  flower  almost  covered  by  the  stamens).  This  is  a  group 
of  pistils.  Study  one  of  these  groups  in  a  flower  from  which  the 
stamens  have  mostly  fallen  off,  and  make  an  enlarged  sketch  of  the 
head  of  pistils.  Remove  some  of  the  pistils  from  a  mature  head, 
and  sketch  a  single  one  as  seen  with  the  magnifying  glass.  Label 
the  little  knob  or  beak  at  the  upper  end  of  the  pistil  stigma,  and  the 
main  body  of  the  pistil  the  ovary.  Make  a  section  of  one  of  the 
pistils,  parallel  to  the  flattened  surfaces,  like  that  shown  in  Fig.  150, 
and  note  the  partially  matured  seed  within. 


CHAPTER    XV 


PLAN  AND   STRUCTURE   OF   THE   FLOWER  AND   ITS 
ORGANS 

208.  Parts  or  Organs  of  the  Flower.  —  Most  showy 
flowers  consist,  like  those  studied  in  the  preceding  chap- 
ter, of  four  circles  or  sets  of  organs,  the  sepals,  petals, 
stamens,  and  pistils.  The  sepals,  taken  together,  consti- 
tute the  calyx ;  the  petals,  taken  together,  constitute  the 
corolla  (Fig.  138).1  Some- 
times it  is  convenient  to  have 
a  word  to  comprise  both  calyx 
and  corolla ;  for  this  the  term 
perianth  is  used.  A  flower 
which  contains  all  four  of 
these  sets  is  said  to  be  com- 
plete. Since  the  work  of  the 
flower  is  to  produce  seed,  and 
seed-forming  is  due  to  the 
cooperation  of  stamens  and 
pistils,  or,  as  they  are  often 
called  from  their  relation  to  the  reproductive  organs  of 
spore-plants,  micro  sporophy  Us  and  macrosporophylls  (see 
Sect.  374),  these  are  known  as  the  essential  organs 
(Fig.  138).  The  simplest  possible  pistil  is  a  dwarfed  and 

1  The  flower  of  the  waterleaf  Hydrophyllum  canadense,  modified  by  the 
omission  of  the  hairs  on  the  stamens,  is  here  given  because  it  shows  so  plainly 
the  relation  of  the  parts. 

197 


cor- 


FIG.  138.  — The  Parts  of  the  Flower. 

cal,  calyx;  cor,  corolla;  st, 

stamens;  p,  pistil. 


198 


FOUNDATIONS   OF   BOTANY 


greatly  modified  leaf  (Sect.  222),  adapted  into  a  seed- 
bearing  organ.  Such  a  pistil  may  be  one-seeded,  as  in 
Fig.  166,  or  several-seeded,  as  in  the  diagrammatic  one 
(Fig.  150) ;  it  is  called  a  carpel.  The  calyx  and  corolla  are 
also  known  as  the  floral  envelopes.  Flowers  which  have 
the  essential  organs  are  called  perfect  flowers.  They  may, 
therefore,  be  perfect  without  being  complete.  Incomplete 
flowers  with  only  one  row  of  parts  in  the 
perianth  are  said  to  be  apetalous  (Fig.  139). 
209.  Regular  and  Symmetrical  Flowers. 
—  A  flower  is  regular  if  all  the  parts  of 
the  same  set  or  circle  aj?e  alike  in  size  and 
shape,  as  in  the  stonecrop  (Fig.  140).  Such 
flowers  as  that  of  the  violet,  the  monkshood, 
FIG.  139.  —  Apetai-  and  the  sweet  pea  (Fig.  141)  are  irregular.. 

cms  Flower  of 

(European)  wild    Symmetrical  flowers  are  those  whose  calyx, 

corolla,    circle    of    stamens,    and    set    of 

carpels  consist  each  of  the  same  number  of  parts,  or  in 

which    the   number  in  every  case    is   a  multiple   of  the 

smallest    number  found    in    any  set.     The    stonecrop   is 


FIG.  140. —  Flower  of  Stonecrop. 
I,  entire  flower  (magnified) ;  II,  vertical  section  (magnified). 

symmetrical,  since  it  has  five  sepals,  five  petals,  ten  sta- 
mens, and  five  carpels.     Roses,  mallows,  and  mignonette 


STRUCTURE  OF  THE  FLOWER  AND  ITS  ORGANS     199 


are  familiar  examples  of  flowers  which  are  unsymmet- 
rical  because  they  have  a  large,  indefinite  number  of 
stamens  ;  the  portulaca  is  unsymmetrical,  since  it  has  two 
divisions  of  the  calyx,  five  or  six  petals,  and  seven  to 
twenty  stamens. 

210.  The  Receptacle.  —  The  parts  of  the  flower  are 
borne  on  an  expansion  of  the  peduncle,  called  the  recep- 
tacle. Usually,  as  in  the  flower  of  the  grape  (Fig.  250), 
this  is  only  a  slight  enlargement  of  the  peduncle,  but  in 


FIG.  141.  — Irregular  Corolla  of 
Sweet  Pea. 

,  side  view  ;  B,  front  view  ;  s,  stand- 
ard  ;  w  w,  wings  ;  fc,  keel. 


the  lotus  and  the  magnolia  the  receptacle  is  of  great  size, 
particularly  after  the  petals  have  fallen  and  the  seed  has 
ripened.  The  receptacle  of  the  rose  (Fig.  142)  is  hollow, 
and  the  pistils  arise  from  its  interior  surface. 

211.  Imperfect  or  Separated  Flowers.  —  The  stamens 
and  pistils  may  be  produced  in  separate  flowers,  which 
are,  of  course,  imperfect.  This  term  does  not  imply  that 
such  flowers  do  their  work  any  less  perfectly  than  others, 
but  only  that  they  have  not  both  kinds  of  essential  organs. 
In  the  very  simple  imperfect  flowers  of  the  willow  (Fig. 
143)  each  flower  of  the  catkin  (Fig.  131)  consists  merely 


200  FOUNDATIONS   OF   BOTANY 

of  a  pistil  or  a  group  of  (usually  two)  stamens,  springing 
from  the  axil  of  a  small  bract. 

Staminate  and  pistillate  flowers  may  be  borne  on  differ- 
ent plants,  as  they  are  in  the  willow,  or  they  may  be 
borne  on  the  same  plant,  as  in  the  hickory  and  the  hazel, 
among  trees,  or  in  the  castor-oil  plant,  Indian  corn,  and 
the  begonias.  When  staminate  and  pistillate  flowers  are 
borne  on  separate  plants,  such  a  plant  is  said  to  be 
dicecious,  that  is,  of  two  households ;  when  both  kinds  of 
flower  appear  on  the  same  individual,  the  plant  is  said 
to  be  monoecious,  that  is,  of  one  household. 

212,  Study  of  Imperfect  Flowers.  —  Examine,  draw,  and  describe 
the  imperfect  flowers  of  some  of  the  following  dioecious  plants  and 
one  of  the  monoecious  plants  : l 

f  early  meadow  rue. 

Dioecious  plants ^  willow. 

I  poplar. 

f  walnut,  oak,  chestnut. 

Monoecious  plants ^  hickory,  alder,  beech. 

i  birch,  hazel,  begonia. 

213.  Union  of   Similar   Parts  of  the  Perianth.  —  The 

sepals  may  appear  to  join  or  cohere  to  form  a  calyx  which 
is  more  or  less  entirely  united  into  one  piece,  as  in  Figs. 
139  and  148.  In  this  case  the  calyx  is  said  to  be  gamo- 
sepalous,  that  is,  of  wedded  sepals.  In  the  same  way  the 
corolla  is  frequently  gamopetalous,  as  in  Figs.  144-148. 
Frequently  the  border  or  limb  of  the  calyx  or  corolla  is 
more  or  less  cut  or  lobed.  In  this  case  the  projecting 

1  For  figures  or  descriptions  of  these  or  allied  flowers  consult  Gray's 
Manual  of  Botany,  Emerson's  Trees  and  Shrubs  of  Massachusetts,  NewhalPs 
Trees  of  the  Northern  United  States,  or  Le  Maout  and  Decaisne's  Traite 
General  de  Botanique. 


STRUCTURE  OF  THE  FLOWER  AND  ITS  ORGANS    201 


portions   of  the  limb   are   known  as  divisions,   teeth,   or 

lobes.1     Special  names  of  great  use  in  accurately  describing 

plants  are  given  to  a  large  number  of  forms  of  the  gamo- 
petalous  corolla.  Only  a  few  of  these 
names  are  here  given,  in  connection  with 
the  figures. 

When  the  parts  of  either  circle  of  the 
perianth  are  wholly  unconnected  with  each 
other,  that  is,  polysepalous  or  polypetalous, 
such  parts  are  said  to  be  distinct. 

214.  Parts  of  the  Stamen  and  the  Pistil. 
—  The  stamen  usually  consists  of  a  hollow 
portion,  the  anther  (Fig.  149,  a),  borne  on  a 
stalk  called  the  filament  (Fig.  149,  /),  which 
is  often  lacking.  Inside  the  anther  is  a  pow- 

dery or  pasty  substance  called  pollen  or  microspores  (Sect. 

374).     The  pistil  usually  consists  of  a  small  chamber,  the 

ovary,  which  contains  the  ovules,  macrospores  (Sect.  374), 

or  rudimentary  seeds,  a  slen- 

der portion  or  stalk,  called  the 

style,  and  at  the  top  of  this  a 

ridge,  knob,  or    point  called 

the  stigma.     These  parts  are 

all  shown   in  Fig.  150.      In 

many    pistils    the    stigma   is 

borne  directly  on  the  ovary. 
215.   Union  of  Stamens  with 

Each  Other.  —  Stamens   may 

be    Wholly   Unconnected    with  J,staminate  flower;  B,  pistillate  flower. 

1  It  would  not  be  safe  to  assume  that  the  gamosepalous  calyx  or  the  garno- 
petalous  corolla  is  really  formed  by  the  union  of  separate  portions,  but  it  is 
very  convenient  to  speak  of  it  as  if  it  were. 


FIG.  MS.  -Flowers  of  wmow. 

(Magnified.) 


202 


FOUNDATIONS   OF    BOTANY 


each  other  or  distinct,  or  they  may  cohere  by  their  fila- 
ments into  a  single  group,  when  they  are  said  to  be 
monadelphous,  of  one  brotherhood  (Fig. 
151),  into  two  groups  (diadelphous)  (Fig. 
152),  or  into  many  groups.  In  some 
flowers  the  stamens  are  held  together  in 
a  ring  by  their  coherent  anthers  (Fig. 
153). 

216.  Union  of  Pistils.  —  The  pistils 
may  be  entirely  separate  from  each 
other,  distinct  and  simple,  as  they  are 

FIG.  144. -Bell-Shaped      .  jf 

corolla  of  Beii-Fiower    in  the  buttercup  and  the  stonecrop,  or 
(Campanula).  several  may  join  to  form  one  compound 

pistil  of  more  or  less  united  carpels.  In  the  latter  case 
the  union  generally  affects  the  ovaries,  but  often  leaves 
the  styles  separate,  or  it  may  result 
in  joining  ovaries  and  styles,  but 
leave  the  stigmas  separate  or  at  any 
rate  lobed,  so  as  to  show  of  how 
many  separate  carpels  the  compound 
pistil  is  made  up.  Even  when  there 
is  no  external  sign  to  show  the 
compound  nature  of 
the  pistil,  it  can  usu- 
ally be  recognized 
from  the  study  of 
a  cross-section  of  the 

FIG.  145.  — Salver-Shaped 
Corolla    of    Jasmine.     OVary. 
(Magnified.)  ^      Cells    Qf    ^ 

Ovary ;   Placentas.  —  Compound    ovaries    are    very    com- 
monly several-celled,  that  is,  they  consist  of  a  number  of 


FIG.  146. 

Wheel-Shaped  Corolla 
of  Potato. 


STRUCT!' KK   OF  TIIK   FLO \VKIl   AND   ITS  ORGANS    203 


separate  cells1  or  chambers,  more  scientifically  known 
as  locules.  Fig.  154,  B,  shows  a  three-celled  ovary 
seen  in  cross-section.  The  ovules  are  not  borne  indis- 
criminately by  any  part  of  the  lining  of  the  ovary.  In 
one-celled  pistils  they  frequently  grow  in  a  line  running 
along  one  side  of  the  ovary,  as  in  the  pea  pod  (Fig.  271). 
The  ovule-bearing  line  is  called  a  placenta  ;  in  compound 
pistils  there  are  commonly  as  many  placentas  as  there  are 


stiff— c& 


sty — 


FIG.  147.— Tubu- 
lar Corolla,  from 
Head  of  Bache- 
lor's Button. 


FIG.  149.  —  Parts  of  a 
FIG.  148.  — Labi-  Stamen, 

ate  or  Ringent  A,  front ;  B,  back  ;  a,  an- 
Corolla  of  Dead  ther ;  c,  connective; 
Nettle.  /,  filament. 


FIG.  150.  —  Parts 
of  the  Pistil. 

ov,  ovary. 

sty,  style. 
stig,  stigma. 


separate  pistils  joined  to  make  the  compound  one.  Pla- 
centas on  the  wall  of  the  ovary,  like  those  in  Fig.  154,  A, 
are  called  parietal  placentas  ;  those  which  occur  as  at  B, 
in  the  same  figure,  are  said  to  be  central,  and  those  which, 
like  the  form  represented  in  O  of  the  same  figure,  consist 
of  a  column  rising  from  the  bottom  of  the  ovary  are 
called  free  central  placentas. 

1  Notice  that  the  word  cell  is  here  used  in  an  entirely  different  sense  from 
that  in  which  it  has  been  employed  in  the  earlier  chapters  of  this  book.  As 
applied  to  the  ovary,  it  means  a  chamber  or  compartment. 


204 


FOUNDATIONS   OF   BOTANY 


218.  Union  of  Separate  Circles.  —  The  members  of  one 
of  the  circles  of  floral  organs  may  join  those  of  another 
circle,  thus  becoming  adnate,  adherent,  or  consolidated. 
In  Fig.  139'  the  calyx  tube  is  adnate  to  the 
ovary.  In  this  case  the  parts  of  the  flower  do 
not  all  appear  to  spring  from  the  receptacle. 
Fig.  155  illustrates  three  common  cases  as 
regards  insertion  of  the  parts  of  the  flower. 
In  I  they  are  all  inserted  on  the  receptacle, 
and  the  corolla  and  stamens  are  said  to  be 
hypogynous,  that  is,  beneath  the  pistil.  In  II 
^IQ  petals  and  the  stamens  appear  as  if  they 


stamens  of     had  grown  fast  to  the  calyx  for  some  distance, 
so  that  they  surround  the  pistil,  and  they  are 


Ill 


therefore  said  to  be  perigynous,  that  is, 
around  the  pistil.  In  III  all  the  parts  are 
free  or  unconsolidated,  except  the  petals 
and  stamens  ;  the  stamens  may  be  described 
as  epipetalous,  that  is,  growing  on  the  petals. 

Sometimes  some  or  all 

of  the  other  parts  stand 

upon  the  ovary,  and  such 
FIG.  152.  —  Diadeiphous  parts  are  said  to  be  epig- 

Stamens  of  Sweet  Pea.       ^^     ^^     ^     Qn     ^ 

ovary,  like  the  petals  and  stamens  of  the 
white  water-lily  (Fig.  156). 

219.    Floral   Diagrams.  —  Sections    (real  FlG<  153.  —stamens 
or  imaginary)   through   the   flower  length-     of  a  Thistle>  with 

e  Anthers     united 

wise,  like  those  of  Fig.  155,  help  greatly     into  a  King. 

in  giving  an  accurate  idea  of  the  relative  «,  united  anthers;/, 

r  .  .  filaments,  bearded 

position  of  the  floral   organs.      Still    more     on  the  sides. 


STRUCTURE  OF  THE   FLOWER  AND  ITS  ORGANS    205 


important  in  this  way  are  cross-sections,  which  may  be 
recorded  in  diagrams  like  those  of  Fig.  157. l  In  con- 
structing such  diagrams  it 
will  often  be  necessary  if) 
suppose  some  of  the  parts 
of  the  flower  to  be  raised 
or  lowered  from  their  true 

FIG.  154.  -Principal  Types  of  Placenta.  position,     SO     as     to      bring 

A .  parietal  placenta  ;  £,  central  placenta ;  .-,              .     ,                 -i            -,     .. 

C,  free  central  placenta;^  and  B,  trans-  them     into     Such     relations 

verse  sections  ;  C,  longitudinal  section.  ^}ia^   a^  could   be   Cut    by  a 

single   section.     This  would,  for  instance,   be    necessary 
in  making  a  diagram  for  the  cross-section  of  the  flower 


i  ii  in 

FIG.  155.— Insertion  of  the 

Floral  Organs. 

I,  Hypogynous,  all  the  other  parts  on 
the  receptacle,  beneath  the  pistil ; 
II,  Perigynous,  petals  and  stamens 
apparently  growing  out  of  the  calyx , 
around  the  pistil ;  III,  corolla 
hypogynous,  stamens  epipetalous. 


FIG.  156.  — White  Water-Lily.  The 
inner  petals  and  the  stamens  grow- 
ing from  the  ovary. 


of  the   white  water-lily,  of  which  a  partial  view  of  one 
side  is  shown  in  Fig.  156.2 

1  For  floral  diagrams  see  Le  Maout  ami  Decaisne's   Traitt  General  de 
Botanique,  or  Eichler's  Bliithendiagramme. 

2  It  is  best  to  begin  practice  on  floral  diagrams  with  flowers  so  firm  and 
large  that  actual  sections  of  them  may  be  cut  with  ease  and  the  relations  of 
the  parts  in  the  section  readily  made  out.    The  tulip  is  admirably  adapted 
for  this  purpose. 


206 


FOUNDATIONS    OF   BOTANY 


Construct  diagrams  of  the  longitudinal  section  and  the 
transverse  section  of  several  large  flowers,  following  the 
method   indicated   in   Figs.    155    and   157,    but   making 
•  the   longitudinal   section    show 

the  interior  of   the  ovary.1     It 
is  found  convenient  to   distin- 


I  II  III 

FIG.  157.  —  Diagram  of  Cross-Sections  of  Flowers. 

I,  columbine  ;  II,  heath  family  ;  III,  iris  family.  In  each  diagram  the  dot  along- 
side the  main  portion  indicates  a  cross-section  of  the  stem  of  the  plant.  In 
II  every  other  stamen  is  more  lightly  shaded,  because  some  plants  of  the 
heath  family  have  five  and  some  ten  stamens. 

guish  the  sepals  from  the  petals  by  representing  the 
former  with  midribs.  The  diagrammatic  symbol  for  a 
stamen  stands  for  a  cross-section  of  the  anther,  and  that 
for  the  pistil  is  a  section  of  the  ovary.  If  any  part  is 
lacking  in  the  flower  (as  in  the  case  of  flowers  which 
have  some  antherless  filaments)  the  missing  or  abortive 
organ  may  be  indicated  by  a  dot.  In  the  diagram  of  the 
Iris  Family  (Fig.  157,  III)  the  three  dots  inside  the  flower 
indicate  the  position  of  a  second  circle  of  stamens,  found 
in  most  flowers  of  monocotyledons  but  not  found  in  this 
family. 

1  Among  the  many  excellent  early  flowers  for  this  purpose  may  be  men- 
tioned trillium,  bloodroot,  dogtooth  violet,  marsh  marigold,  buttercup,  tulip 
tree,  horse-chestnut,  Jeffersonia,  May-apple,  cherry,  apple,  crocus,  tulip, 
daffodil,  primrose,  wild  ginger,  cranesbill,  locust,  bluebell. 


STRUCTURE   OF  THE   FLOWER   AM)   ITS   ORGANS     207 

220.    Review  Summary  of  Chapter  XV.1 

(1  <l^A>fx 
2.  o  OiA^Mfc^ 
8.' 


Kinds  as  regards  numerical  plan 

Kinds  as  regards  similarity  of  parts  of  the  same 
circle    . 


Parts  of  a  stamen 


Parts  of  a  pistil    . 


Stamens  as  regards  union  with  each  other    . 

,  ^svJL^^JUl 

Pistils  as  regards  union  with  each  other  .     .     .     .       •{  0  a  ., 

v  £.\~JLj-*****foj(y****- 

Degree  of  union  of  separate  circles j 

1  Illustrate  by  sketches. 


CHAPTER    XVI 


TRUE    NATURE    OF   FLORAL    ORGANS;     DETAILS    OF 
THEIR    STRUCTURE;  FERTILIZATION 

221.  The  Flower  a  Shortened  and  greatly  Modified 
Branch.  —  In  Chapter  VIII,  the  leaf-bud  was  explained 
as  being  an  undeveloped  branch,  which  in  its  growth 
would  develop  into  a  real  branch  (or  a  prolongation  of 
the  main  stem).  Now,  since  flower-buds  appear  regularly 


FlG.  158.  —  Transition  from  Bracts  to  Sepals  in  a  Cactiis  Flower. 

either  in  the  axils  of  leaves  or  as  terminal  buds,  there  is 
reason  to  regard  them  as  of  similar  nature  to  leaf-buds. 
This  would  imply  that  the  receptacle  corresponds  to  the 
axis  of  the  bud  shown  in  Fig.  86,  and  that  the  parts  of 
the  flower  correspond  to  leaves.  There  is  plenty  of  evi- 
dence that  this  is  really  true.  Sepals  frequently  look 
very  much  like  leaves,  and  in  many  cacti  the  bracts 

208 


TRUE    NATURE   OF   FLORAL   ORGANS 


209 


about  the  flower  are  so  sepal-like  that  it  is  impossible  to 
tell  where  the  bracts  end  and  the  sepals  begin  (Fig.  158). 
The  same  thing  is  true  of  sepals  and  petals  in  such  flowers 
as  the  white  water-lily.  In  this  flower  there  is  a  remark- 
able series  of  intermediate  steps,  ranging  all  the  way  from 
petals,  tipped  with  a  bit  of  anther,  through  stamens  with 
a  broad  petal-like  filament,  to  regular  stamens,  as  is  shown 
in  Fig.  159,  E,  F,  6r,  H.  The  same  thing  is  shown  in 


PIG.  159.  —  Transitions  from  Petals  to  Stamens  in  White  Water-Lily. 
E,  F,  G,  H,  various  steps  between  petal  and  stamen. 

many  double  roses.  In  completely  double  flowers  all  the 
essential  organs  are  transformed  by  cultivation  into  petals. 
In  the  flowers  of  the  cultivated  double  cherry  the  pistils 
occasionally  take  the  form  of  small  leaves,. and  some  roses 
turn  wholly  into  green  leaves. 

Summing  up,  then,  we  know  that  flowers  are  altered 
and  shortened  branches  :  (1)  because  flower-buds  have  as 
regards  position,  the  same  kind  of  origin  as  leaf-buds ; 
(2)  because  all  the  intermediate  steps  are  found  between 
bracts,  on  the  one  hand,  and  stamens,  on  «the  other  ;  (3) 


210  FOUNDATIONS   OF   BOTANY 

because  the  essential  organs  are  found  to  be  replaced  by 
petals  or  even  by  green  leaves. 

The  fact  that  leaves  should  be  so  greatly  modified  as 
they  are  in  flowers  and  given  work  to  do  wholly  different 
from  that  of  the  other  kinds  of  leaves  so  far  studied  need 
not  strike  one  as  exceptional.  In  many  of  the  most  highly 
developed  plants  below  the  seed-plants,  organs  correspond- 
ing to  flowers  are  found,  and  these  consist  of  modified 
leaves,  set  apart  for  the  work  of  reproducing  (Sect.  367). 

222.  Mode  of  Formation  of  Stamens  and  Pistils  from 
Leaves.  —  It  is  hardly  possible  to  state,  until  after  Chap- 
ter XXIII  has  been  studied,  how  stamens  stand  related 
to  leaves.1 

The  simple  pistil  or  carpel  is  supposed  to  be  made  on 
the  plan  of  a  leaf  folded  along  the  midrib  until  its  margins 
touch,  like  the  cherry  leaf  in  Fig.  87.  But  the  student 
must  not  understand  by  this  statement  that  the  little 
pistil  leaf  grows  at  first  like  an  ordinary  leaf  and  finally 
becomes  folded  in.  The  united  leaf-margins  near  the  tip 
would  form  the  stigma,  and  the  placenta  would  correspond 
to  the  same  margins,  rolled  slightly  inwards,  extending 
along  the  inside  of  the  inflated  leaf-pouch.  Place  several 
such  folded  leaves  upright  about  a  common  center,  and 
their  cross-section  would  be  much  like  that  of  J5  in  Fig. 
154.  Evidence  that  carpels  are  really  formed  in  this  way 
may  be  gained  "from  the  study  of  such  fruits  as  that  of 
the  monkshood  (Fig.  168),  in  which  the  ripe  carpels  may 
be  seen  to  unfold  into  a  shape  much  more  leaf-like  than 
that  which  they  had  while  the  pistil  was  maturing.  What 

1  "The  anther  answers  exactly  to  the  spore-cases  of  the  ferns  and  their 
allies,  while  the  filament  is  a  small  specialized  leaf  to  support  it."  For  a 
fuller  statement,  see*Potter  and  Warming's  Systematic  Botany,  pp.  236,  237. 


TRUE  NATURE  OF  FLORAL  ORGANS 


211 


really  occurs  is  this :  the  flower-bud,  as  soon  as  it  has 
developed  far  enough  to  show  the  first  rudiments  of  the 
essential  organs,  contains  them  in  the  form  of  minute 
knobs.  These  are  developed  from  the  tissues  of  the  plant 
in  the  same  manner  as  are  the  knobs  in  a  leaf-bud,  which 
afterwards  become  leaves  (Fig.  87,  II)  ;  but  as  growth 
and  development  progress 
in  the  flower-bud,  its  con- 
tents soon  show  themselves 
to  be  stamens  and  pistils  (if 
the  flower  is  a  perfect  one). 
223.  The  Anther  and  its 
Contents. — Some  of  the 
shapes  of  the  anthers  may 
be  learned  from  Figs.  149  T  TT 

and  160.1    The  shape  of  the    FiG- 16°— Modes  of  ^charging Poiien. 


berry);  III,  by  a  pore  at  the  top  of  each 
anther-lobe  (nightshade). 


anther  and  the  way  in  which 
it  opens  depend  largely  upon 
the  way  in  which  the  pollen 
is  to  be  discharged  and  how  it  is  carried  from  flower  to 
flower.  The  commonest  method  is  to  have  the  anther- 
cells  split  lengthwise,  as  in  Fig.  160,  I.  A  few  anthers 
open  by  trap-doors  like  valves,  as  in  II,  and  a  larger 
number  by  little  holes  at  the  top,  as  in  III. 

The  pollen  in  many  plants  with  inconspicuous  flowers, 
as  the  evergreen  cone-bearing  trees,  the  grasses,  rushes, 
and  sedges,  is  a  fine,  dry  powder.  In  plants  with  showy 
flowers  it  is  often  somewhat  sticky  or  pasty.  The  forms 
of  pollen  grains  are  extremely  various.  Fig.  161  will 
serve  to  furnish  examples  of  some  of  the  shapes  which 


1  See  -Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  II,  pp.  86-95. 


212 


FOUNDATIONS   OF   BOTANY 


the  grains  assume  ;  c  in  the  latter  figure  is  perhaps  as 
common  a  form  as  any.  Each  pollen  grain  consists  mainly 
of  a  single  cell,  and  is  covered  by  a  moderately  thick  outer 
wall  and  a  thin  inner  one.  Its  contents  are  thickish 
protoplasm,  full  of  little  opaque  particles  and  usually 
containing  grains  of  starch  and  little  drops  of  oil.  The 
knobs  on  the  outer  coat,  as  shown  in  Fig.  161  5,  mark 


a  bed 

FIG.  161.  —  Pollen  Grains.     (Very  greatly  magnified.) 
«,  pumpkin  ;  6,  enchanter's  nightshade  ;  c,  Alhuca  ;  d,  pink  ;  e,  hibiscus. 

the  spots  at  which  the  inner  coat  of  the  grain  is  finally 
to  burst  through  the  outer  one,  pushing  its  way  out  in 
the  form  of  a  slender,  thin-walled  tube.1 

224.  The  Formation  of  Pollen  Tubes. --This  can  be 
studied  in  pollen  grains  which  have  lodged  on  the  stigma 
and  there  been  subjected  to  the  action  of  its  moist  surface. 
It  is,  however,  easier  to  cause  the  artificial  production  of 
the  tubes. 

EXPERIMENT    XXXVIII 

Production  of  Pollen  Tubes.  —  Place  a  few  drops  of  suitably  diluted 
syrup  with  some  fresh  pollen  in  a  concave  cell  ground  in  a  micro- 
scope slide ;  cover  with  thin  glass  circle  ;  place  under  a  bell-glass, 
with  a  wet  cloth  or  sponge,  to  prevent  evaporation  of  the  syrup,  and 
set  aside  in  a  warm  place,  or  merely  put  some  pollen  in  syrup  in  a 

1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  II,  pp.  95-104. 


FERTILIZATION 


213 


watch  crystal  under  the  bell-glass.  Examine  from  time  to  time  to 
note  the  appearance  of  the  pollen  tubes.  Try  several  kinds  of 
pollen  if  possible,  using  syrups  of  various  strengths.  The  follow- 
ing kinds  of  pollen  form  tubes  readily  in  syrups  of  the  strengths 
indicated. 

Tulip  . 1  to  3  per  cent. 

Narcissus 3  to  5       " 

Cytisus  canariensis  (called  Genista  by  florists)  15       " 

Chinese  primrose          .          .          .          .          .  10        " 

Sweet  pea l  .         ...  .         .     10  to  15       " 

Tropseolum 1        .  ....  15       " 

9 

225.  Microscopical  Structure  of  the  Stigma  and  Style.  — 
Under  a  moderate  power  of  the  microscope  the  stigma  is 
seen  to  consist  of  cells  set  irregularly  over  the  surface, 
and  secreting  a  moist  liquid  to 
which  the  pollen  grains  adhere  (Fig. 
162).  Beneath  these  superficial  cells 
and  running  down  through  the  style 
(if  there  is  one)  to  the  ovary  is 
spongy  parenchyma.  In  some  pistils 
the  pollen  tube  proceeds  through 
the  cell  walls,  which  it  softens  by 
means  of  a  substance  which  it  exudes 
for  that  purpose.  In  other  cases 
(Fig.  163)  there  is  a  canal  or  passage, 
along  which  the  pollen  tube  travels 
on  its  way  to  the  ovule. 


FIG.  162.  —  Stigma  of  Thorn- 
Apple  (Datura)  with  Pollen. 
(Magnified.) 


1  The  sweet-pea  pollen  and  that  of  Tropseolum  are  easier  to  manage  than 
any  other  kinds  of  which  the  author  has  personal  knowledge.  If  a  concaved 
slide  is  not  available,  the  cover-glass  may  be  propped  up  on  bits  of  the  thin- 
nest broken  cover-glasses.  From  presence  of  air  or  some  other  reason,  the 
formation  of  pollen  tubes  often  proceeds  most  rapidly  just  inside  the  margin 
of  the  cover-glass. 


214 


FOUNDATIONS   OF   BOTANY 


226.  Fertilization.  —  By  fertilization  in  seed-plants  the 
botanist  means  the  union  of  a  generative  cell  from  a  pol- 
p  len  grain  with  that  of  an  egg-cell 
at  the  apex  of  the  embryo  sac 
(Fig.  165).  This  process  gives 
rise  to  a  cell  which  contains 
material  derived  from  the  pollen 
and  from  the  egg-cell.  In  a 
great  many  plants  the  pollen, 
in  order  to  accomplish  the  most 
successful  fertilization,  must 
come  from  another  plant  of  the 
same  kind,  not  from  the  indi- 
vidual which  bears  the  ovules 
that  are  being  fertilized. 

Pollen  tubes  begin  to  form 
soon  after  pollen  grains  lodge 
on  the  stigma.  The  time  re- 

Fm.  163. — Pollen  Grains  producing  ,    »         ,,  , 

Tubes,  on  stigma  of  a  Lily.  (Much  quired  for  the  process  to  begin 
magnified.)  varies    in    different    kinds    of 

g,  pollen  grains  ;  t,  pollen  tubes  ;  p,       -,  ... 

of  stigma  ;c,  canal  or  pas-  plants,  requiring  in  many  cases 
twenty-four  hours  or  more.  The 
length  of  time  needed  for  the 
pollen  tube  to  make  its  way 
through  the  style  to  the  ovary 
depends  upon  the  length  of  the 

FIG.  104. -Pollen  Grain  of  Snow-       .    le    and   Qther  con(iitionS.       In 
flake  (Leucoium)  producing  a  Pol-        » 
len  Tube  with  Two  Naked  Genera-    the    CrOCUS,     which    has    a    Style 

several  inches  long,  the  descent 
takes  from  one  to  three  days. 

Finally  the  tube  penetrates  the  opening  at  the  apex  of 


a,ge  running  toward  ovary. 


FERTILIZATION 


215 


the  ovule  m,  in  Fig.  165,  reaches  one  of  the  cells  shown 
at  e,  and  transfers  a  generative  cell  into  this  egg-cell.  The 
latter  is  thus  enabled  to 
divide  and  grow  rapidly 
into  an  embryo.  This 
the  cell  does  by  forming 
cell-walls  and  then  in- 
creasing by  continued 
subdivision,  in  much  the 
same  way  in  which  the 
cells  at  the  growing  point 
near  the  tip  of  the  root, 
or  those  of  the  cambium 
layer,  subdivide.1 

227.  Nature  of  the 
Fertilizing  Process.— 
The  necessary  feature  of 
the  process  of  fertiliza- 
tion is  the  union  of  the 
essential  contents  of  two 
cells  to  form  a  new  one, 
from  which  the  future 
plant  is  to  spring.  This 
kind  of  union  is  found 
to  occur  in  many  cryp- 
t  o  g  a  m  s  (Chapters 
XX-XXII),  resulting 
in  the  production  of 
a  spore  capable  of  grow- 
ing into  a  complete  plant  like  that  which  produced  it. 

1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  II,  pp.  401-420. 


FIG.  165.  —  Diagrammatic  Representation  of 
Fertilization  of  an  Ovule. 

i,  inner  coating  of  ovule  ;  o,  outer  coating  of 
ovule;  p,  pollen  tube,  proceeding  from  one 
of  the  pollen  grains  on  the  stigma  ;  c,  the 
place  where  the  two  coats  of  the  ovule 
blend.  (The  kind  of  ovule  here  shown  is 
inverted,  its  opening  m  being  at  the  bottom, 
and  the  stalk  /  adhering  along  one  side  of 
the  ovule.)  a  to  e,  embryo  sac,  full  of  pro- 
toplasm ;  a,  so-called  antipodal  cells  of  em- 
bryo sac  ;  n,  central  nucleus  of  the  embryo 
sac ;  e,  nucleated  cells,  one  of  which,  the 
egg-cell,  receives  the  essential  contents  of 
the  pollen  tube ;  /,  f  uniculus  or  stalk  of 
ovule ;  m,  opening  into  the  ovule. 


216  FOUNDATIONS   OF    BOTANY 

228,  Number  of  Pollen  Grains  to  Each  Ovule.  —  Only 
one  pollen  tube  is  necessary  to  fertilize  each  ovule,  but 
so  many  pollen  grains  are  lost  that  plants  produce  many 
more  of  them  than  of  ovules.  The  ratio,  however,  varies 
greatly.  In  the  night-blooming  cereus  there  are  about 
250,000  pollen  grains  for  30,000  ovules,  or  rather  more 
than  8  to  1,  while  in  the  common  garden  wistaria  there 
are  about  7000  pollen  grains  to  every  ovule,  and  in  Indian 
corn,  the  cone-bearing  evergreens,  and  a  multitude  of  other 
plants,  many  times  more  than  7000  to  1.  These  differences 
depend  upon  the  mode  in  which  the  pollen  is  carried  from 
the  stamens  to  the  pistil. 


CHAPTER   XVII 
THE    STUDY    OF    TYPICAL   FRUITS 

229.  A  Berry,  the  Tomato.1  —  Study  the    external  form  of   the 
tomato,  and  make  a  sketch  of  it  showing  the  persistent  calyx  and 
peduncle. 

Cut  a  cross-section  at  about  the  middle  of  the  tomato.  Note  the 
thickness  of  the  epidermis  (peel  oif  a  strip)  and  of  the  wall  of  the 
ovary.  Note  the  number,  size,  form,  and  contents  of  the  cells  of 
the  ovary.  Observe  the  thickness  and  texture  of  the  partitions 
between  the  cells.  Sketch. 

Note  the  attachments  of  the  seeds  to  the  placentas  and  the  gelati- 
nous, slippery  coating  of  each  seed. 

The  tomato  is  a  typical  berry,  but  its  structure  presents  fewer 
points  of  interest  than  are  found  in  some  other  fruits  of  the  same 
general  character,  so  the  student  will  do  well  to  spend  a  little  more 
time  on  the  examination  of  such  fruits  as  the  orange  or  the  lemon. 

230.  A  Hesperidium,  the  Lemon.  —  Procure  a  large  lemon  which 
is  not  withered,  if  possible  one  which  still  shows  the  remains  of  the 
calyx  at  the  base  of  the  fruit. 

Note  the  color,  general  shape,  surface,  remains  of  the  calyx, 
knob  at  portion  formerly  occupied  by  the  stigma.  Sketch  the  fruit 
about  natural  size.  Examine  the  pitted  surface  of  the  rind  with 
the  magnifying  glass  and  sketch  it.  Remove  the  bit  of  stem  and 
dried-up  calyx  from  the  base  of  the  fruit;  observe,  above  the  calyx, 
the  knob  or  disk  on  which  the  pistil  stood.  Note  with  the  magni- 
fying glass  and  count  the  minute  whitish  raised  knobs  at  the  bottom 
of  the  saucer-shaped  depression  left  by  the  removal  of  the  disk. 
What  are  they  ? 

1  Fresh  tomatoes,  not  too  ripe,  are  to  be  used,  or  those  which  have  been  kept 
over  from  the  previous  summer  in  formalin  solution.  The  very  smallest 
varieties,  such  as  are  often  sold  for  preserving,  are  as  good  for  study  as  the 
larger  kinds. 

217 


218  FOUNDATIONS   OF   BOTANY 

Make  a  transverse  section  of  the  lemon,  not  more  than  a  fifth  of 
the  way  down  from  the  stigma  end  and  note  : 

(1)  The  thick  skin,  pale  yellow  near  the  outside,  white  within. 

(2)  The  more  or  less  wedge-shaped  divisions  containing  the  juicy 
pulp  of  the  fruit.     These  are  the  matured  cells  of  the  ovary ;  count 
these. 

(3)  The  thin  partition  between  the  cells. 

(4)  The  central  column  or  axis  of  white  pithy  tissue. 

(5)  The   location    and   attachment  of  any   seeds   that   may  be 
encountered  in  the  section. 

Make  a  sketch  to  illustrate  these  points,  comparing  it  with 
Fig.  171. 

Study  the  section  with  the  magnifying  glass  and  note  the  little 
spherical  reservoirs  near  the  outer  part  of  the  skin,  which  contain  the 
oil  of  lemon  which  gives  to  lemon  peel  its  characteristic  smell  and 
taste.  Cut  with  the  razor  a  thin  slice  from  the  surface  of  a  lemon 
peel,  some  distance  below  the  section,  and  at  once  examine  the 
freshly  cut  surface  with  a  magnifying  glass  to  see  the  reservoirs, 
still  containing  oil,  which,  however,  soon  evaporates.  On  the  cut 
surface  of  the  pulp  (in  the  original  cross-section)  note  the  tubes  in 
which  the  juice  is  contained.  These  tubes  are  not  cells,  but  their 
walls  are  built  of  cells.  Cut  a  fresh  section  across  the  lemon,  about 
midway  of  its  length  and  sketch  it,  bringing  out  the  same  points 
which  were  shown  in  the  previous  one.  The  fact  that  the  number 
of  ovary  cells  in  the  fruit  corresponds  with  the  number  of  minute 
knobs  in  the  depression  at  its  base  is  due  to  the  fact  that  these 
knobs  mark  the  points  at  which  nbro-vascular  bundles  passed  from 
the  peduncle  into  the  cells  of  the  fruit,  carrying  the  sap  by  which 
the  growth  of  the  latter  was  maintained. 

Note  the  toughness  and  thickness  of  the  seed-coats.  Taste  the 
kernel  of  the  seed. 

Cut  a  very  thin  slice  from  the  surface  of  the  skin,  mount  in 
water,  and  examine  with  a  medium  power  of  the  microscope. 
Sketch  the  cellular  structure  shown  and  compare  it  with  the  sketch 
of  the  corky  layer  of  the  bark  of  the  potato  tuber. 

Of  what  use  to  the  fruit  is  a  corky  layer  in  the  skin  ?  (See  Sect. 
453  for  further  questions.) 


THE    STUDY   OF   TYPICAL    FRUITS  219 

231.  A  Legume,  the  Bean-Pod.1  —  Lay  the  pod  flat  on  the  table 
and  make  a  sketch  of  it,  about  natural  size.     Label  stigma,  style, 
ovary,  calyx,  peduncle. 

Make  a  longitudinal  section  of  the  pod,  at  right  angles  to  the 
plane  in  which  it  lay  as  first  sketched,  and  make  a  sketch  of  the 
section,  showing  the  partially  developed  seeds,  the  cavities  in  which 
they  lie,  and  the  solid  portion  of  the  pod  between  each  bean  and 
the  next. 

Split  another  pod,  so  as  to  leave  all  the  beans  lying  undisturbed 
on  one-half  of  it  and  sketch  that  half,  showing  the  beans  lying  in 
their  natural  position  and  the  funiculus  or  stalk  by  which  each  is 
attached  to  the  placenta ;  compare  Fig.  271. 

Make  a  cross-section  of  another  pod,  through  one  of  the  beans, 
sketch  the  section,  and  label  the  placenta  (formed  by  the  united 
edges  of  the  pistil  leaf)  and  the  midrib  of  the  pistil  leaf. 

Break  off  sections  of  the  pod  and  determine,  by  observing  where 
the  most  stringy  portions  are  found,  where  the  fibre-vascular  bundles 
are  most  numerous. 

Examine  some  ripe  pods  of  the  preceding  year,2  and  notice  where 
the  dehiscence,  or  splitting  open  of  the  pods,  occurs,  whether  down 
the  placental  edge,  ventral  suture,  the  other  edge,  dorsal  suture,  or 
both. 

232.  An  Akene,  the  Fruit  of  Dock.  —  Hold  in  the  forceps  a  ripe 
fruit  of  any  of  the  common  kinds  of  dock,3  and  examine  with  the 
magnifying  glass.    Note  the  three  dry,  veiny,  membranaceous  sepals 
by  which  the  fruit  is  enclosed.     On  the  outside  of  one  or  more  of 
the  sepals  is  found  a  tubercle  or  thickened  appendage  which  looks 
like  a  little  seed  or  grain.     Cut  off  the  tubercles  from  several  of  the 
fruits,  put  these,  with  some  uninjured  ones,  to  float   in  a  pan  of 
water,  and  watch  their  behavior  for  several  hours.     What  is  appar- 
ently the  use  of  the  tubercle  ? 

1  Any  species  of  bean  (Phaseolus)  will  answer  for  this  study.    Specimens 
in  the  condition  known  at  the  markets  as  "  shell-beans  "  would  be  best,  but 
these  are  not  obtainable  in  spring.     Ordinary  "  string-beans  "  will  do. 

2  Which  may  be  passed  round  for  that  purpose.    They  should  have  been 
saved  and  dried  the  preceding  autumn. 

8  Rumex  crispus,  R.  obtusifohits,  or  R.  verticillatus.  This  should  have 
been  gathered  and  dried  the  preceding  summer. 


220  FOUNDATIONS   OF   BOTANY 

Of  what  use  are  the  sepals,  after  drying  up  ?  Why  do  the  fruits 
cling  to  the  plant  long  after  ripening? 

Carefully  remove  the  sepals  and  examine  the  fruit  within  them. 
What  is  its  color,  size,  and  shape?  Make  a  sketch  of  it  as  seen  with 
the  magnifying  glass.  Note  the  three  tufted  stigmas,  attached  by 
slender  threads  to  the  apex  of  the  fruit.  What  does  their  tufted 
shape  indicate  ? 

What  evidence  is  there  that  this  seed-like  fruit  is  not  really  a 
seed? 

Make  a  cross-section  of  a  fruit  and  notice  whether  the  wall  of 
the  ovary  can  be  seen,  distinct  from  the  seed-coats.  Compare  the 
dock  fruit  in  this  respect  with  the  fruit  of  the  buttercup,  shown  in 
Fig.  166.  Such  a  fruit  as  either  of  these  is  called  an  akene. 


CHAPTER    XVIII 
THE   FRUIT1 

233.  What  constitutes  a  Fruit.  —  It  is  not  easy  to  make 
a  short  and  simple  definition  of  what  botanists  mean  by 
the  texm  fruit.     It  has  very  little  to  do  with  the  popular 
use  of  the  word.     Briefly  stated,  the    definition  may  be 
given  as  follows  :    The  fruit  consists  of  the  matured  ovary 
and  contents,  together  with  any  intimately  connected  parts. 
Botanically  speaking,  the  bur  of  beggar's  ticks  (Fig.  273), 
the  three-cornered  grain  of  buckwheat,  or  such  true  grains 
as  wheat  and  oats,  are  as  much  fruits  as  is  an  apple  or  a 
peach. 

The  style  or  stigma  sometimes  remains  as  an  important 
part  of  the  fruit  in  the  shape  of  a  hook,  as  in  the  common 
hooked  crowfoot ;  or  in  the  shape  of  a  plumed  appendage, 
as  in  the  virgin's  bower,  often  called  wild  hops.  The 
calyx  may  develop  hooks,  as  in  the  agrimony,  or  plumes, 
as  in  the  thistle,  the  dandelion,  lettuce,  and  many  other 
familiar  plants.  In  the  apple,  pear,  and  very  many  ber- 
ries, the  calyx  becomes  enlarged  and  pulpy,  often  consti- 
tuting the  main  bulk  of  the  mature  fruit.  The  receptacle 
not  infrequently,  as  in  the  apple,  forms  a  more  or  less 
important  part  of  the  fruit. 

234.  Indehiscent  and    Dehiscent    Fruits.  —  All   of   the 
fruits  considered  in  the  next  three  sections  are  indehiscent, 

1  See  Gray's  Structural  Botany,  Chapter  VII,  also  Kerner  and  Oliver's 
Natural  History  of  Plants,  Vol.  II,  pp.  427-438. 

221 


222 


FOUNDATIONS    OF   BOTANY 


FIG.  166.  —  Akenes  of  a  Buttercup. 

A,  head  of  akenes  ;  £,  section  of  a  single 

akene  (magnified)  ;  a,  seed. 


that   is,    they   remain    closed    after   ripening.      Dehiscent 
fruits  when  ripe  open  in  order  to  discharge  their  seeds. 

The  three  classes  which  im- 
mediately follow  Sect.  237 
belong  to  this  division. 

235.  The  Akene.  —  The 
one-celled  and  one-seeded 
pistils  of  the  buttercup, 
strawberry,  and  many  other 
flowers,  ripen  into  a  little 
fruit  called  an  akene  (Fig. 
166).  Such  fruits,  from 
their  small  size,  their  dry 
consistency,  and  the  fact  that  they  never  open,  are  usually 
taken  for  seeds  by  those  who  are  not  botanists. 

In  the  group  of  plants  to  which  the  daisy,  the  sunflower, 
and  the  dandelion  belong,  the  akenes  consist  of  the  ovary 
and  the  adherent  calyx  tube.  The  limb  of  the  calyx  is 
borne  on  the  summit  of  many  akenes,  sometimes  in  the  form 
of  teeth,  sometimes  as  a  tuft 
of  hairs  or  bristles  (Fig.  267).  ^ 

236.  The   Grain.  —  Grains, 
such  as  corn,  wheat,  oats,  bar- 
ley, rice,  and  so  on,  have  the 
interior    of    the    ovary    com- 
pletely filled  by  the  seed,  and 
the  seed-coats  and  the  wall  of 
the  ovary  are  firmly  united,  as 
shown  in  Fig.  6. 

237.  The  Nut.  —  A  nut  (Fig.   167)    is    larger   than  an 
akene,  usually  has  a  harder  shell,  and  commonly  contains 


FIG.  167.  — Chestnuts. 


THE    FRUIT 


223 


a  seed  which  springs  from  a  single  ovule  of  one  cell  of  a 
compound  ovary,  which  develops  at  the  expense  of  all  the 
other  ovules.  The  chestnut-bur  is  a  kind  of  involucre, 
and  so  is  the  acorn-cup.  The  name 
nut  is  often  incorrectly  applied  in 
popular  language;  for  example,  the 
so-called  Brazil-nut  is  really  a  large 
seed  with  a  very  hard  testa. 

238.    The    Follicle.  —  One-celled, 
simple  pistils,  like  those  of  the  marsh 
marigold,  the  columbine,  and  a  good 
many  other,  plants,   often    produce  a 
FIG.  168. -Group  of  Tom- fruit    which   dehisces    along   a   single 
cies  and  a  single  Foiiicie  suture   usually  the  ventral  one.     Such 

of  the  Monkshood.  \  J 

a  fruit  is  called  a  follicle  (Fig.  168). 

239.  The  Legume.  —  A    legume   is    a   one-celled   pod, 
formed  by  the  maturing  of  a  simple  pistil,  which  dehisces 
along  both  of  its  sutures,  as  already  seen  in  the  case  of 
the  bean  pod,  and  illus- 
trated in  Fig.  271. 

240.  The  Capsule.  - 
The  dehiscent  fruit 
formed  by  the  ripening 
of  a  compound  pistil  is 
called  a  capsule.     Such 
a  fruit  may  be  one- 
celled,  as  in  the  linear 
pod    of    the    celandine 
(Fig.  271),  or  several- 
celled,  as  in  the  fruit  of  the  poppy,  the  morning-glory, 
and  the  jimson  weed  (Fig.  271). 


FIG.  16U.  —  Winged  Fruits. 
I,  elm  ;  II,  maple. 


224 


FOUNDATIONS   OF   BOTANY 


241.  Dry  Fruits  and  Fleshy  Fruits.  —  In  all  the  cases 
discussed  or  described  in  Sects.  238-240,  the  wall  of  the 
ovary  (and  the  adherent  calyx  when  present)  ripen  into 
tissues  which  are  somewhat  hard  and  dry.     Often,  how- 
ever, these  parts  become  developed  into  a  juicy  or  fleshy 
mass  by  which  the  seed  is  surrounded  ;  hence  a  general 
division  of  fruits  into  dry  fruits  and  fleshy  fruits. 

242.  The  Stone-Fruit.  —  In  the  peach,  apricot,  plum,  and 
cherry,  the  pericarp  or  wall  of  the  ovary,  during  the  proc- 
ess of  ripening,  becomes  con- 
verted into  two  kinds  of  tissue, 
the   outer   portion   pulpy  and 
edible,    the    inner    portion    of 
almost    stony    hardness.       In 
common   language    the    hard- 
ened inner  layer  of  the  peri- 
carp,   enclosing    the    seed,    is 
called    the    stone    (Fig.    170), 
hence  the  name  stone-fruits. 

243.  The  Pome.  —The  fruit 
of  the  apple,  pear,  and  quince  is  called  a  pome.  It  con- 
sists of  a  several-celled  ovary,  —  the  seeds  and  the  tough 
membrane  surrounding  them  in  the  core,  —  enclosed  by  a 
fleshy,  edible  portion  which  makes  up  the  main  bulk  of 
the  fruit  and  is  formed  from  the  much-thickened  calyx, 
with  sometimes  an  enlarged  receptacle.  In  the  apple  and 
the  pear  much  of  the  fruit  is  receptacle. 

244.  The  Pepo  or  Gourd-Fruit.  —  In  the  squash,  pump- 
kin, and  cucumber,  the  ripened  ovary,  together  with  the 
thickened  adherent  calyx,  makes  up  a  peculiar  fruit  (with 
a  firm  outer  rind)  known  as  the  pepo.  The  relative  bulk 


Km.  170.  — Peach.    Longitudinal 
Section  of  Fruit. 


THE   FRUIT 


225 


of  enlarged  calyx  and  of  ovary  in  such  fruits  is  not  always 
the  same. 

How  does  the  amount  of  material  derived  from  fleshy 
and  thickened  placentae  in  the  squash  compare  with  that 
in  the  watermelon  ? 

245.  The   Berry.  —  The    berry   proper,    such    as    the 
tomato,  grape,  persimmon,  gooseberry,  currant,  and  so  on, 
consists   of  a  rather  thin- 
skinned,    one-   to    several- 
celled,  fleshy  ovary  and  its 

contents.  In  the  first  three 

cases  above  mentioned  the 

calyx  forms  no  part  of  the     «•   ^S^SQi 

fruit,  but  it  does  in  the  last 

two,  and  in  a  great  number 

of  berries. 

The  gourd-fruit  and  the 
.hesperidium,  such  as  the 
orange  (Fig.  171),  lemon, 
and  lime,  are  merely  de- 
cided modifications  of  the 
berry  proper. 

246.  Aggregate    Fruits.  —  The     raspberry,    blackberry 
(Fig.  172),  and  similar  fruits  consist  of  many  carpels,  each 
of  which  ripens  into  a  part  of  a  compound  mass,  which, 
for  a  time  at  least,  clings  to  the  receptacle.     The  whole  is 
called  an  aggregate  fruit. 

To  which  one  of  the  preceding  classes  does  each  unit  of 
a  blackberry  or  of  a  raspberry  belong  ? 

What  is  the  most  important  difference  in  structure 
between  a  fully  ripened  raspberry  and  a  blackberry  ? 


FIG.  171.  —  Cross-Section  of  an  Orangr. 
a,  axis  of  fruit  with,  dots  showing  cut-off 
ends  of  nbro-vascular  bundles  ;  p,  parti- 
tion between  cells  of  ovary  ;  S,  seed  ; 
c,  cell  of  ovary,  filled  with  a  pulp  com- 
posed of  irregular  tubes,  full  of  juice  ; 
o,  oil  reservoirs  near  outer  surface  of 
rind  ;  e,  corky  layer  of  epidermis. 


226 


FOUNDATIONS   OF   BOTANY 


247.  Accessory  Fruits  and  Multiple  Fruits.  —  Not  infre- 
quently, as  in  the  strawberry  (Fig.  172),  the  main  bulk  of 
the  so-called  fruit  consists  neither  of  the  ripened  ovary 
nor  its  appendages.  Such  a  combination  is  called  an 
accessory  fruit. 

Examine  with  a  magnifying  glass  the  surface  of  a  small,  unripe 
strawberry,  then  that  of  a  ripe  one,  and  finally  a  section  of  a  ripe 
one,  and  decide  where  the  separate  fruits  of  the  strawberry  are  found, 
what  kind  of  fruits  they  are,  and  of  what  the  main  bulk  of  the  straw- 
berry consists. 

The  fruits  of  two  or  more  separate  flowers  may  blend 
into  a  single  mass,  which  is  known  as  a  multiple  fruit. 
Perhaps  the  best-known  edible  examples  of  this  are  the 


i  ii  in 

FlG.  172.— I,  Strawberry  ;  II,  Raspberry  ;  III,  Mulberry. 

mulberry  (Fig.  172)  and  the  pineapple.  The  last-named 
fruit  is  an  excellent  instance  of  the  seedless  condition 
which  not  infrequently  results  from  long-continued  culti- 
vation. 

248.  Summary.  —  The  student  may  find  it  easier  to 
retain  what  knowledge  he  has  gained  in  regard  to  fruits  if 
he  copies  the  following  synopsis  of  the  classification  of 
fruits,  and  gives  an  example  of  each  kind. 


THE   FRUIT 


227 


Fruits    < 


C  Simple. 

Aggregate. 
Composition                     J    . 
|  Accessory. 

[Multiple. 

I1- 

Fleshy              J.  2. 
I3' 

Texture 

Stone 

fl. 

\  I 

U 

fl. 

Indehiscent      J  2. 

Mode  of 

I3- 

disseminating  seed 

fi. 

Dehiscent         <  2. 

I 

CHAPTER    XIX 
THE    CLASSIFICATION   OF   PLANTS1 

24=9.  Natural  Groups  of  Plants.  —  One  does  not  need  to 
be  a  botanist  in  order  to  recognize  the  fact  that  plants 
naturally  fall  into  groups  which  resemble  each  other  pretty 
closely,  that  these  groups  may  be  combined  into  larger 
ones  the  members  of  which  are  somewhat  alike,  and  so  on. 
For  example,  all  the  bulb-forming  spring  buttercups  2  which 
grow  in  a  particular  field  may  be  so  much  alike  in  leaf, 
flower,  and  fruit  that  the  differences  are  hardly  worth 
mentioning.  The  tall  summer  buttercups  3  resemble  each 
other  closely,  but  are  decidedly  different  from  the  bulbous 
spring-flowering  kind,  and  yet  are  enough  like  the  latter 
to  be  ranked  with  them  as  buttercups.  The  yellow 
water-buttercups4  resemble  in  their  flowers  the  two 
kinds  above  mentioned,  but  differ  from  them  greatly  in 
habit  of  growth  and  in  foliage,  while  still  another,  a 
very  small-flowered  kind,5  might  fail  to  be  recognized 
as  a  buttercup  at  all. 

The  marsh  marigold,  the  hepatica,  the  rue  anemone, 
and  the  anemone  all  have  a  family  resemblance  to  butter- 
cups,6 and  the  various  anemones  by  themselves  form 
another  group  like  that  of  the  buttercups. 

1  See  Warming  and  Potter's  Systematic  Botany,  Strasburger,  Noll,  Schenk, 
and  Schimper's  Text-Book  of  Botany,  Part  II,  or  Kerner  and  Oliver,  Vol.  II, 
pp.  616-790.  2  R.  bulbosus.  3  R.  acris.  4  R.  multifidus.  5  R.  abortivus. 

6  Fresh  specimens  or  herbarium  specimens  will  show  this. 

228 


THE   CLASSIFICATION  OF   PLANTS  229 

250.  Genus  and  Species.  —  Such  a  group  as  that  of  the 
buttercups    is  called  a  genus   (plural  genera),   while  the 
various  kinds  of  buttercups  of  which  it  is  composed  are 
called  species.    The  scientific  name  of  a  plant  is  that  of  the 
genus  followed  by  that  of  the  species.     The  generic  name 
begins  with  a  capital,  the  specific  does  not,  unless  it  is  a 
substantive.     After  the  name  comes  the  abbreviation  for 
the  name  of  the  botanist  who  is  authority  for  it;  thus  the 
common  elder  is  Sambucus  canadensis,  L.,  L.  standing  for 
Linnaeus.     Familiar  examples  of   genera  are   the  Violet 
genus,  the  Rose  genus,  the  Clover  genus,  the  Golden-rod 
genus,  the  Oak  genus.     The  number  of  species  in  a  genus 
is  very  various,  —  the    Kentucky   Coffee-tree  genus  con- 
tains only  one  species,  while  the  Golden-rod  genus  com- 
prises more  than  forty  species  in  the  northeastern  United 
States  alone. 

251.  Hybrids If  the  pollen  of  a  plant  of  one  species 

is  placed  on  the  stigma  of  a  plant  of  the  same  genus  but  a 
different  species,  no  fertilization  will  usually  occur.     In  a 
large  number  of  cases,  however,  the  pistil  will  be  ferti- 
lized, and  the  resulting  seed  will  often  produce  a  plant 
intermediate  between  the  two  parent  forms.     This  proc- 
ess  is    called    hybridization,   and    the    resulting    plant  a 
hybrid.     Many   hybrid   oaks   have  been  found   to  occur 
in  a  state  of  nature,  and  hybrid  forms  of  grapes,  orchids, 
and  other    cultivated   plants,  are  produced   by  horticul- 
turists at  will. 

252.  Varieties.  —  Oftentimes  it  is  desirable  to  describe 
and  give  names  to  subdivisions  of  species.     All  the  culti- 
vated kinds  of  apple  are  reckoned  as  belonging  to  one  spe- 
cies, but  it  is  convenient  to  designate  such  varieties  as  the 


230  FOUNDATIONS   OF   BOTANY 

Baldwin,  the  Bellflower,  the  Rambo,  the  Gravenstein,  the 
Northern  Spy,  and  so  on.  Very  commonly  varieties  do 
not,  as  horticulturists  say,  "  come  true,"  that  is  to  say,  the 
seeds  of  any  particular  variety  of  apple  not  only  are  not 
sure  to  produce  that  variety,  but  they  are  nearly  sure  to 
produce  a  great  number  of  widely  different  sorts.  Varie- 
ties which  will  reproduce  themselves  from  the  seed,  such 
as  pop-corn,  sweet  corn,  flint-corn,  and  so  on,  are  called 
races. 

Only  long  and  careful  study  of  plants  themselves  and 
of  the  principles  of  classification  will  enable  any  one  to 
decide  on  the  limits  of  the  variety,  species,  or  genus,  that 
is,  to  determine  what  plants  shall  be  included  in  a  given 
group  and  what  ones  shall  be  classed  elsewhere. 

253.  Order  or  Family.  —  Genera  which  resemble  each 
other  somewhat  closely,  like  those  discussed  in  Sect.  249, 
are  classed  together  in  one  order  or  family.  The  particu- 
lar genera  above  mentioned,  together  with  a  large  number 
of  others,  combine  to  make  up  the  Crowfoot  family.  In 
determining  the  classification  of  plants  most  points  of 
structure  are  important,  but  the  characteristics  of  the 
flower  and  fruit ,  outrank  others  because  they  are  more 
constant,  since  they  vary  less  rapidly  than  the  characteris- 
tics of  roots,  stems,  and  leaves  do  under  changed  condi- 
tions of  soil,  climate,  or  other  surrounding  circumstances. 
Mere  size  or  habit  of  growth  has  nothing  to  do  with  the 
matter,  so  the  botanist  finds  no  difficulty  in  recognizing 
the  strawberry  plant  and  the  apple  tree  as  members  of 
the  same  family. 

This  family  affords  excellent  illustrations  of  the  mean- 
ing of  the  terms  genus,  species,  and  so  on.  Put  in  a 


THE    CLASSIFICATION   OF   PLANTS 


231 


tabular  form,  some  of  the  subdivisions  of  the  Rose  family 
are  as  follows  : 


j  Peach  species  (many  varieties). 

Plum  genus         Garden  plum  species  (many  varieties). 
I  Wild  black  cherry  species. 
I  Garden  red  cherry  species  (many  varieties). 

'  Dwarf   wild  rose 


Rose  genus 


Pear  genus 


species. 
Sweet-brier  species. 

India  rose  species 
Damask  rose  species. 

Pear  species 


Apple  species 


Tea  variety. 
Pompon  variety,  etc. 

C  Seckel  variety. 
Bartlett  variety. 
Sheldon  variety,  etc. 

Baldwin  variety. 
Greening  variety. 
Bellflower  variety. 
Northern  Spy  variety, 
etc. 


254,  Grouping  of  Families.  —  Families  are  assembled 
into  classes,  and  these  again  into  larger  groups.  The 
details  of  the  entire  plan  of  classification  are  too  compli- 
cated for  any  but  professional  botanists  to  master,  but  an 
outline  of  the  scheme  may  be  given  in  small  space. 

The  entire  vegetable  kingdom  is  divided  into  two  great 
divisions,  the  first  consisting  of  cryptogams  or  spore-plants, 
the  second  of  phanerogams  or  seed-plants.  Here  the  rela- 
tions of  the  various  subdivisions  may  best  be  shown  by  a 
table.1 

1  This  is,  of  course,  only  for  consultation,  not  to  be  committed  to  memory. 


232 


UNDATIONOF  BOTANY 


Vegetable  Kingdom 


~        <4>        O        ^> 

•g    «  1 1  -^  I 

«        O      •<      h«g      r<      r<        53 

(^  O  O  Q,  ft^  O,  flq 


^2 
o 

<o 

1  | 

IH 

1 

i 

g 

'SLi 

3 

^  ,2 

^^ 

a 

^ 

hH 

s 

. 

05 

C£I 

c* 

§ 

^ 

1 

GROUP  1 

MYXOTHALLOP 

or  plasmodial  \ 

'  , 

hH 

CH 
t> 

§ 

e 

THALLOPHYT 

^  t, 

11 

«o 

1 

^> 

)-H 
1—  I 

Cu, 
P 

0 

<5 

BRYOPHYTES  01 

//A:e  plant, 
GROUP  11 

PTERIDOPHYT] 

fern-like  plai 

nclusive  of  the  tha 

.  v  

C4 

S 

l 


DIVISION  II 

PHANEROGAMS  ou 

SEED-PLANTS 


THE    CLASSIFICATION    OF    PLANTS  233 


CLASS  I 

GYMNOSPERMS  or  seed-plants  with  naked  ova- 
ries, such  as  pines,  spruces,  cedars,  and  many 
other  evergreen  trees. 

f  SUBCLASS  I 


CLASS  II 
ANGIOSPERMS  or 

seed-plants  with 
closed  ovaries 


MONOCOTYLEDONQUS 

PLANTS 

SUBCLASS  II 
DICOTYLEDONOUS 

PLANTS 


256.  The  Groups  of  Cryptogams.  —  The  student  is  not 
to  suppose  that  the  arrangement  of  cryptogams  into  the 
four  great  groups  given  in  the  preceding  table  is  the  only 
way  in  which  they  could  be  classed.     It  is  simply  one 
way  of  dividing  up  the  enormous  number  of  spore-bearing 
plants  into  sections,  each  designated  by  marked  character- 
istics of  *its  own.     But  the  amount  of  difference  between 
one  group  and  another  is  not  always  necessarily  the  same. 
The    pteridophytes    and   the    bryophytes    resemble   each 
other   much  more  closely  than  the  latter  do  the  thallo- 
phytes,  while  the  myxothallophytes  are  but  little  like  other 
plants  and  it  is  extremely  probable  that  they  are  really 
animals. 

The  classes  given  in  the  table  do  not  embrace  all  known 
cryptogams,  but  only  those  of  which  one  or  more  repre- 
sentatives are  described  or  designated  for  study  in  this 
book.  Lichens  in  one  sense  hardly  form  a  class,  but  it  is 
most  convenient  to  assemble  them  under  a  head  by  them- 
selves, on  account  of  their  extraordinary  mode  of  life,  a 
partnership  between  algae  and  fungi. 

257.  The  Classes  of  Seed-Plants.  —  The  gymnosperms 
are  much  less  highly  developed   than  other  seed-plants. 


234  FOUNDATIONS   OF   BOTANY 

The  angiosperms  constitute  the  great  majority  of  seed- 
plants  (or,  as  they  have  been  more  commonly  called, 
flowering  plants).  Only  one  family  of  gymnosperms  (the 
Conifer ce)  is  described  in  Part  III  of  this  book,  though 
there  are  other  families  of  great  interest  to  the  botanist, 
but  with  no  representatives  growing  wild  in  the  Northern 
United  States. 

When  people  who  are  not  botanists  speak  of  plants 
they  nearly  always  mean  angiosperms.  This  class  is  more 
interesting  to  people  at  large  than  any  other,  not  only  on 
account  of  the  comparatively  large  size  and  the  con- 
spicuousness  of  the  members  of  many  families,  but  also 
on  account  of  the  attractiveness  of  the  flowers  and  fruit 
of  many.  Almost  all  of  the  book  which  precedes  the 
present  chapter  (except  Chapter  XII)  has  been  occupied 
with  seed-plants. 

Seed-plants  of  both  classes  frequently  offer  striking 
examples  of  adaptation  to  the  conditions  under  which 
they  live,  and  these  adaptations  have  lately  received  much 
study,  and  are  now  treated  as  a  separate  department  of 
botany  (see  Part  II). 


CHAPTER   XX 
TYPES    OF  CRYPTOGAMS;    THALLOPHYTES 

258,  The   Group   Thallophytes.  —  Under  this  head  are 
classed  all    the  multitude    of   cryptogams  which  have  a 
plant-body  without  true  roots,  stems,  or  leaves.     Such  a 
plant-body  is  called  a  thallus.     In  its  simplest  form  it  con- 
sists of  a  portion  of  protoplasm  not  enclosed  in  a  cell-wall 
and  without  much  of  any  physiological  division  of  labor 
among  its  parts  (Fig.  125).     Only  a  little  less  simple  are 
such  enclosed  cells  as  that  of  Pleurococcus  (Sect.  278)  or 
one  of  the  segments  of  Oscillatoria  (Sect.  268).    The  most 
complex  thallophytes,  such  as  the  higher  algse  and  fungi, 
have  parts  definitely  set  aside  for  absorption  of  food  and 
for  reproduction.     The  latter  is  sometimes  accomplished 
by  more    than  one  process  and  is  occasionally  aided  by 
some  provision  for  scattering  the  reproductive  bodies  or 
spores  about  when  they  are  mature. 

259.  Spores. —  Before   beginning   the   study  of   spore- 
plants  it  is  well  for  the  student  to  know  what  a  spore  is. 
A  spore  is  a  cell  which  becomes  free  and  capable  of  develop- 
ing into  a  new  plant.     Spores  are  produced  in  one  of  two 
ways :  either  asexually,  from  the  protoplasm  of  some  part 
of  the  plant  (often  a  specialized  spore-producing  portion), 
or  sexually,  by  the  combination  of  two  masses  of  proto- 
plasm, from  two  separate  plants,  or  from  different  parts  of 
the  same  plant. 

235 


236  FOUNDATIONS   OF   BOTANY 

Asexually  produced  spores  are  sometimes  formed,  each 
by  the  condensation  of  the  protoplasm  of  a  single  cell,  as 
shown  in  Fig.  174,  E.  They  are  also  formed  by  the  con- 
tents of  spore-cases  breaking  up  into  many  spores  (Fig. 
173,  B]  Fig.  210,  D).  Spores  are  sometimes  produced  by 
the  spontaneous  division  of  a  mass  of  protoplasm  into  a 
small  definite  number  of  segments  (Fig.  188,  t).  Spores 
which  have  the  power  of  moving  (swimming)  freely  are 
known  as  zoo  spores  (Fig.  179,  j5). 

Sexually  produced  spores  are  formed  in  many  ways. 
One  of  the  simplest  modes  is  that  shown  in  Fig.  178, 
resulting  in  zygospores.  Other  methods  are  illustrated  in 
Figs.  185  and  187.1 

THE    STUDY   OF    SLIME  MOULDS2 

260.  Occurrence.  —  Slime  moulds  occur  in  greenhouses,  in  tan- 
yards,  or  on  old  logs  and  decaying  leaves  in  woods.     They  may  be 
cultivated  in  the  laboratory. 

They  have  been  described  in  their  vegetative  condition  on  page  179. 

261.  Examination  with  the  Magnifying  Glass.  —  Stemonitis   is  one 
of  the  most  available  genera  to  illustrate  the  fruiting  of  slime  moulds. 
At-  maturity  the  motile  protoplasm  of  the  vegetative  stage  quickly 
transforms  itself  into  numerous  sporangia  or  spore-cases  with  dust- 
like  spores.     With  the  naked  eye  and  with  a  magnifying  glass  note 
the  color,  form,  and  feathery  appearance  of  the  spore-case  of  Stemo- 
nitis.    The  outer  wall  disappears  at  an  early  stage,  leaving  only  an 
inner   structure    and   spores.     Sketch    the  general  outline  under  a 
magnifying  glass. 

262.  Examination  with  the  Microscope.  —  With  a  low  power  of 
the  microscope  sketch  the  network  of  branching  hairs  which  com- 
pose the  structure  of  the  sporangium.     Note  the  presence  or  absence 

1  See  Vine's  Student's  Text-Book  of  Botany,  pp.  68-71, 
3  This  should  logically  precede  Sect.  358. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES 


237 


of  a  central  column.  Have  any  of  the  branches  free  tips  ?  With  a 
power  of  250  or  more  examine  the  spores.  A  much  higher  power 
may  be  used  to  advantage.  Describe  the  surface  of  the  spore. 


THE    STUDY   OF   BACTERIA 

263.    Occurrence.  —  "  Bacteria  may  occur  anywhere  but  not  every- 
where."   Tn  water,  air,  soil,  and  almost  any  organic  substance,  living 


FIG.  173.  —  Spore-Cases  of  Slime  Moulds. 

A,  a  group  of  spore-cases  of  Arcyrla ;  Ji,  a  spore-case  of  Trichia,  bursting  open 
and  exposing  its  spores  to  the  wind,  x  20  ;  C,  threads  of  the  same,  with  spores 
between  them,  x  250. 

or  dead,  some  species  of  plant  belonging  to  the  group  Bacteria,  may 
occur.  A  small  bunch  of  hay  placed  in  a  tumbler  of  water  will,  at  a 
suitable  temperature,  yield  an  abundant  crop  in  a  few  days  or  hours. 
Raw  peas  or  beans  soaked  for  a  week  or  two  in  water  in  a  warm 
place  will  afford  a  plentiful  supply. 

264.  Cultures.  —  Pure  cultures  of  bacteria  are  commonly  made  in 
some  preparation  of  gelatine  in  sterilized  test-tubes.  Boiled  potatoes 
serve  a  good  purpose  for  simple  (but  usually  not  pure)  cultures. 

Select  a  few  small  roundish  potatoes  with  skins  entire  and  boil 
in  water  for  a  sufficient  time  to  cook  them  through.  Cut  them  in 
halves  with  a  knife  well  scalded  or  sterilized,  i.e.,  freed  from  all  living 


238  FOUNDATIONS   OF   BOTANY 

organisms  in  a  flame,  and  lay  each  on  a  saucer,  with  cut  surface  up, 
covering  each  with  a  glass  tumbler.  The  tumblers  and  saucers 
should  be  well  scalded  or  kept  in  boiling  water  for  half  an  hour  and 
used  without  wiping.  Sterilization  may  be  improved  by  baking 
them  in  an  oven  for  an  hour. 

265.  Inoculation.  —  The  culture  media  prepared  as  above  may 
now  be  inoculated.  Uncover  them  only  when  necessary  and  quickly 
replace  the  cover.  Scrape  a  little  material  from  the  teeth,  tongue, 
kitchen  sink,  floor  of  house  or  schoolroom,  or  any  other  place  you 
may  desire  to  investigate.  With  the  point  of  a  knife  blade  or  a 
needle  sterilized  in  a  flame,  inoculate  a  particle  of  the  material  to  be 
cultivated  into  the  surface  of  one  of  the  potatoes.  Several  cultures 


D  E 

FIG.  174.  —  Bacteria  stained  to  sliow  Cilia. 

A,  Bacillus  subtilis ;  E,  Bacillus  typhi  (the  bacillus  of  typhoid  fever) ;  C,  Bacillus 
tetani  (the  bacillus  which  causes  lockjaw) ;  D,  Spirillum  undula;  E,  Bacillus 
tetani  forming  spores.  (All  five  are  magnified  1000  diameters.) 

may  be  made  in  this  way  and  one  or  more  left  uninoculated  as 
checks.  Another  may  be  left  uncovered  in  the  air  for  half  an  hour. 
Others  may  be  made  with  uncovered  potatoes.  Number  each  culture 
and  keep  a  numbered  record. 

Keep  watch  of  the  cultures,  looking  at  them  daily  or  oftener.  As 
soon  as  any  change  is  noticed  on  the  surface  of  a  culture,  make  a 
descriptive  note  of  it  and  continue  to  record  the  changes  which  are 
seen.  Note  the  color  of  the  areas  of  growth,  their  size,  outline,  ele- 
vation above  the  surface,  and  any  indications  of  wateriness.  Any 
growth  showing  peculiar  colors  or  other  characters  of  special  inter- 
est may  be  inoculated  into  freshly  prepared  culture  media,  using 
any  additional  precautions  that  are  practicable  to  guard  against 
contamination. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     239 

266.  Microscopic  Examination.  —  Examine  some  of  the  cultures. 
Place  a  particle  of  the  growth  on  a  slide,  dilute  it  with  a  drop  of 
clear  water,  and  place  a  cover-glass  over  it.  Examine  with  the 
highest  obtainable  power  of  the  microscope,  at  least  £  in.  objective. 
Note  the  forms  and  movements,  also  the  sizes  if  practicable,  of  any 
bacteria  that  are  found. 


THE    STUDY   OF   OSCILLATORIA1 

267.  Occurrence.  —  Oscillatoria   may  occur   floating   in  stagnant 
water  or  on  damp  soil  in  ditches,  roadsides,  dooryards,  paths,  or 
pots  in  greenhouses.     Other  nearly  related  plants  occur  on  surfaces 
of  ponds  sometimes  covering  considerable  areas  or  adhering  in  small 
spheres  to  submerged  vegetation.     Algae  of  this  class  are  particu- 
larly noxious  in  water  supplies,  as  they  partake  of  the  nature  of 
bacteria,  to  which  they  are  related. 

268.  Examination  with  the  Microscope.  —  After  washing  a  particle 
of  Oscillatoria  material  in  a  drop  of  water  to  remove  as  much  of  the 
earth  as  possible,  place  it  in  a  clean  drop  of  water,  pull  to  shreds 
with  needles,  cover,  and  examine  under  a  power  of  200  or  more 
diameters. 

Note  the  color  and  compare  it  with  chlorophyll  green. 

The  filament  is  not  one  plant,  but  each  of  the  cells  which  com- 
pose it  is  one  plant.  They  are  packed  together  in  the  filament  like 
coins  and  sometimes  may  be  found  separating  singly.  The  usual 
mode  of  reproduction  is  by  the  separation  of  a  number  of  adhering 
cells  as  a  short  filament  from  one  end  of  a  longer  one,  and  this 
increases  in  length  by  the  dividing  of  its  individual  cells. 

269.  Movement.  —  At  ordinary  temperatures,  favorable  to  growth, 
movement  may  be  observed  in  the  filaments.     Describe  the  move- 
ment.    What  has  it  to  do  with  the  name  of  the  plant? 

1  A  genus  of  the  class  Schizophycese. 


240 


FOUNDATIONS   OF   BOTANY 


THE    STUDY   OF   DIATOMS 

270.    Occurrence.  —  Diatoms  of  different  species  may  be  found  in 
sediment  in  water  in   various  kinds   of   places  or  mixed  with  or 

adhering  to  fresh-water  or  ma- 
rine algse,  in  ponds  and  ditches 
or  on  sand  or  earth  at  the 
bottom  of  clear  brooks.  In  the 
last  place  they  may  be  detected 
with  the  eye,  forming  a  yellow- 
ish coloring.  They  may  often 
be  obtained  by  straining  hy- 
drant water.  Where  diatoms 
have  been  very  abundant  their 
remains  sometimes  form  beds 
of  rock,  and  fossil  diatoms 
compose  some  of  the  polishing 
powders  of  commerce. 

271.  Microscopical  Examina- 
tion of  Diatoms.  —  Place  a  drop 
of  water  containing  diatoms  on 
a  slide  and  put  a  cover-glass 
over  it.  Examine  with  a  power 
of  ^200  or  more  diameters.  Dia- 
toms occur  singly,  resembling- 
triangles,  wheels,  boats,  rods, 
and  a  great  variety  of  other 
forms  (Fig.  176),  or  adhering 
in  long  bands,  as  spokes  of  a 
wheel,  etc.  The  boat-shaped 
kinds  are  among  the  common- 
est. The  color  of  the  contents 
is  yellowish.  The  cell-wall  is 
encrusted  with  a  shell  of  silica 
whose  surface  is  covered  with  beautiful  markings,  dots  or  lines, 
which  are  conspicuous  in  some  species,  in  others  so  minute  that  the 
most  powerful  microscopes  are  required  to  detect  them.  By  boiling 


FIG.  175.  —  Schizophycese. 
A,  a  filament  of  Calothrix,  reproducing  by 
hormogonia,  h,  segmented  portions  which 
escape  from  the  sheath  of  the  filament ; 
B,  Rivularia.  (Both  A  and  B  greatly 
magnified.) 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTBS 


241 


in  nitric  acid,  the  cellulose  wall  and  its  contents  may  be  destroyed 
and  the  markings  of  the  siliceous  shell  more  easily  observed.  Each 
diatom  consists  of  a  single  cell. 

272.  Movements  of  Diatoms.  —  Living  diatoms  exhibit  a  peculiar 
power  of  movement.  In.  the  boat-shaped  species  the  movement  is 
much  like  that  of  a  row-boat,  forward  or  backward. 


THE    STUDY    OF    SPIROGYRA 

273.  Occurrence.  —  Spirogyra,  one  of  the  plants  commonly  known 
as  pond-scum,  or  "  frog-spit,"  occurs  widely  distributed  throughout 
the  country  in  ponds,  springs, 

and  clear  streams.  It  is  of  a 
green  or  yellowish-green  color,- 
and  in  sunny  weather  usually 
floats  on  or  Dear  the  surface  of 
the  water,  buoyed  up  by  the 
numerous  oxygen  bubbles  which 
it  sets  free.  It  may  be  found 
flourishing  in  unfrozen  springs, 
even  in  midwinter. 

274.  Examination- with  the 
Magnifying    Glass.1  —  Float    a 
little  of  the  material  in  a  white 
plate,  using  just  water  enough 
to  cover  the  bottom  of  the  latter. 
Study  with  the  magnifying  glass 
and  note  the  green  color  of  the 
threads  and  their  great  length 
as  compared  with  their  thick- 
ness. Are  all  the  filaments  about 
equal  to  each  other  in  diameter  ? 

Handle  a  mass  of  the  material  and  describe  how  it  feels  between 
the  fingers. 

275.  Examination  with  the  Microscope.  —  Mount  in  water  under 
a  large  cover-glass  and  examine  first  with  a  power  of  about  100 

1  Consult  Huxley's  Biology  and  Spalding's  Introduction  to  Botany. 


FIG.  176.  —A  Group  of  Diatoms. 

A,  Achnanthes;  B,Cocconema; 
C,  Meridion;  J>,  Pleurosigma. 


242 


FOUNDATIONS   OF   BOTANY 


diameters,  then  with  a  power  of  200  diameters  or  more.  Note  the 
structure  of  the  filaments.  Of  what  is  each  made  up?  Compare 
with  the  structure  of  Oscillatorla. 

Move  the  slide  so  as  to  trace  the  whole  length  of  several  filaments, 
and,  if  the  unbroken  end  of  one  can  be  found,  study  and  sketch  it. 

Study  with  the  higher  power  a  single 
cell  of  one  of  the  larger  filaments  and 
ascertain  the  details  of  structure.     Try 
to  discover,  by  focusing,  the  exact  shape 
of  the  cell.     How  do  .you  know  that 
the  cells  are  riot  flat?    Count  the  bands 
of  chlorophyll.     The  number  of  bands 
is  an  important  characteristic  in  dis- 
tinguishing one  species  from  another. 
Run  in  five-per-cent  salt  solution  at 
one  edge  of  the  cover-glass  (withdraw- 
ing water  from  the  other  edge  with  a 
bit  of  blotting  paper).     If  any  change 
in  the  appearance  of  the  cell  becomes 
evident,    make   a   sketch  to   show  it. 
What  has  happened   to   the  cell-con- 
tents?     Explain    the    cause    of    the 
FIG.  177.  — Process  of  Cell-Multi- 
plication in  a  Species  of  Pond-     change  by  reference  to  what  you  know 
Scum.  (Considerably  magnified.)      of  osmose. 

On  a  freshly  mounted  slide  run 
under  the  cover-glass  iodine  solution, 
a  little  at  a  time,  and  note  its  action 
on  the  nucleus.  Is  any  starch  shown 


A,  portion  of  a  filament  partly 
separated  at  a  and  completely 
so  at  b ;  B,  separation  nearly 
completed,  a  new  partition  of 
cellulose  formed  at  a;  C, 

another   portion   more  magni-  .  .  0      T£. 

tied,  showing  mucous  covering      to  be  P^Sent?      If  SO,   just   how   IS   it 

distributed  through  the  cell? 

276.    Reproduction  of  Spirogyra.— 

The  reproductive  process  in  Spirogyra 
is  of  two  kinds,  the  simplest  being  a  process  of  Jission,  or  cell- 
division.  The  nucleus  undergoes  a  very  complicated  series  of 
transformations,  which  result  in  the  division  of  the  protoplasmic 
contents  of  a  cell  into  two  independent  portions,  each  of  which  is 
at  length  surrounded  by  a  complete  cell-wall  of  its  own.  In  Fig.  176 


d,  general  cell-wall  c,  and  a 
delicate  membrane  a,  which 
covers  the  cell-contents  6. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES 


243 


the  division  of  the  protoplasm  and  formation  of  a  partition  of 
cellulose  in  a  kind  of  pond-scum  are  shown,  but  the  nucleus  and  its 
changes  are  not  represented. 

Another  kind  of  reproduction,  namely  by  conjugation,  is  found  in 
Spirogyra.  This  process  in  its  simplest  form  is  found  in  such 
unicellular  plants  as  the  desmids 
(Fig.  178).  Two  cells  (apparently 
precisely  alike)  come  in  contact, 
undergo  a  thinning-down  or  absorp- 
tive process  in  the  cell-walls  at  the 
point  of  contact,  and  finally  blend  z. 
their  protoplasmic  cell-contents,  as 
shown  in  the  figure,  to  form  a  mass 
known  as  a  spore,  or  more  accu- 
rately a  zygospore,  from  which,  after 


i  IT 

FIG.  178.  — Conjugation  of  Cells  of  Green  Algaj.     (Much  magnified.) 

I.  Conjugation  of  Desmids.  A,  a  single  plant  in  its  ordinary  condition;  £,  empty 
cell-wall  of  another  individual ;  C,  conjugation  of  two  individuals  to  form  a 
spore  by  union  of  their  cell-contents. 

II.  Conjugation  of  Spirogyra.  A,  two  filaments  of  Spirogyra  side  by  side,  with 
the  contents  of  adjacent  cells  uniting  to  form  spores,  z.  At  the  bottom  of  the 
figure  the  process  is  shown  as  beginning  at  the  top  as  completed,  and  the  cells 
of  one  filament  emptied ;  B,  a  single  filament  of  another  kind  of  Spirogyra, 
containing  two  spores,  one  lettered  z.  (A  magnified  240  diameters,  B  150 
diameters.) 

a  period  of  rest,  a  new  individual  develops.  In  Spirogyra  each 
cell  of  the  filament  appears  to  be  an  individual  and  can  conjugate 
like  the  one-celled  desmids.  It  is  not  easy  to  watch  the  process, 
since  the  spore-formation  takes  place  at  night.  It  is  possible, 


244 


FOUNDATIONS   OF   BOTANY 


however,  to  retard  the  occurrence  of  conjugation  by  leaving  the 
Spirogyra  filaments  in  very  cold  water  over  night,  and  in  this  way 
the  successive  steps  of  the  conjugating  process  may  be  studied  ^by 
daylight.  In  such  ways  the  series  of  phenomena  shown  in  Fig. 
178,  II,  has  been  accurately  followed.  If  the  student  cannot  follow 
these  operations  under  the  microscope,  he  may,  at  least,  by  looking 
over  the  yellower  portions  of  a  mass  of  Spirogyra  find  threads  con- 
taining fully  formed  zygospores,  like  those  shown  in  B,  Fig.  178. 


THE   STUDY   OF   PLEUROCOCCUS 

277.  Occurrence. — Pleurococcus  may   be   found   on   old   fences, 
roofs,  and  many  similar  places,  particularly  on  the  bark  of  the  north 
side  of  trees.    The  individual  plants  cannot  be  detected  by  the  naked 
eye,  but  when  grouped  in  masses  they  form  a  powdery  green  covering 
over  indefinite  areas  of  bark.     Plenty  are  seen  where  it  is  moist. 

278.  Microscopical  Examination  of  Pleurococcus.  —  Scrape  a  minute 
quantity  of  Pleurococcus  from  a  specimen  on  bark,  place  it  in  a  drop 
of  water  on  a  slide,  distributing  it  slightly  in  the  water,  lay  on  it 

a  cover-glass  and  ex- 
amine with  a  power  of 
200  or  more  diameters. 
Sketch  with  the  cam- 
era lucida  one  of  the 
largest  cells,  some  of 
intermediate  size,  and 
one  of  the  smallest, 
beside  several  divisions 
of  the  stage  microm- 
eter. 

Note  the  clearly  de- 
fined cell-wall  of  cel- 
lulose, enclosing  the 
protoplasmic  contents, 
usually  green  through- 
out. Do  any  cells  show  a  nucleus  like  that  in  Fig.  179,  A  ? 


FIG.  179.  — Two  Cells  of  Protococcus. 
(Greatly  magnified.) 

A,  a  spherical  cell  of  the  still  form  ;  B,  a  motile  cell 
with  its  protoplasm  enclosed  in  a  loose  cell-wall  and 
provided  with  two  cilia. 


Test  the  cells  with  iodine  solution  for  starch. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     245 

Note  that  in  reproduction  the  cell-contents  in  many  individuals 
has  divided  into  two  parts  which  become  separated  from  each  other 
by  a  cellulose  partition.  Each  of  these  again  divides,  and  the  proc- 
ess continues  until  thirty-two  or  more  cells  may  be  found  in  one 
mass  or  they  may  fall  apart  at  an  earlier  stage. 

279.  Nutrition  of  Pleurococcus.  —  Pleurococcus  can  flourish  only 
with  an  abundance  of  light  and  moisture.    In  daylight  it  can  absorb 
carbon  dioxide  and  fix  carbon  (giving  off  the  oxygen  at  the  same 
time  as  bubbles  of  oxygen)  and  can  assimilate  mineral  substances. 
It  is  a  capital  example  of  an  individual  cell  capable  of  independent 
existence. 

280.  Motile  Forms.  —  ]STo  motile  form  is  known  in  Pleurococcus. 
Hcematoccus,  often  known  as  Protococcus  (Fig.  179),  is  a  better  object 
for  study  than  Pleurococcus.     It  may  sometimes  be  found  in  water 
of  stagnant  pools,  particularly  those  which  contain  the  drainage  of 
barnyards  or  manure-heaps,  in  mud  at  the  bottom  of  eaves-troughs, 
in  barrels  containing  rain-water,  or  in  water  standing  in  cavities  in 
logs  or  stumps.     Its  presence  is  indicated  by  a  greenish  or  some- 
times by  a  reddish  color.     It  is  sometimes  found  in  an   actively 
swimming  condition,  in  which  case  each  cell  is  called  a  zob'spore. 

THE    STUDY   OF   VAUCHERIA 

281.  Occurrence.  —  Species    of    Vaucheria   are   found   in   ponds, 
streams,  and  pools,  immersed  or  floating  like  Spirogyra  and  at  all 
seasons  may  be  sought  in  greenhouses,  where  they  grow  on  the  moist 
earth  of  beds  and  pots,  forming  a  green  felt. 

282.  Examination  with  the  Magnifying  Glass.  —  The  magnifying 
glass  will  show  the  growth   of    Vaucheria  to  consist  of  numerous 
green  filaments  similar  to  those  of  Spirogyra.     Select  a  small  portion 
and  spread  out  the  filaments  carefully  in  a  drop  of  water  on  a  slide. 
Does  the  glass  reveal  any  indications  of  cross-partitions,  of  branch- 
ing, or  of  fruiting  organs  as  short  lateral  branches  ?     Does  it  show 
the  form  or  arrangement  of  the  green  coloring  matter? 

283.  Examination   with   the   Microscope.  —  Prepare    as   directed 
for  the  magnifying  glass  and  place  a  cover-glass  over  the  prepara- 
tion, with  sufficient  water.     With  the  lowest  power    observe  the 


246 


FOUNDATIONS   OF   BOTANY 


continuity  of  the  cell-cavity  and  (in  young  plants  growing  on  soil) 
search  for  root-like  portions,  in  those  growing  in  water  for  branch- 
ing portions,  and  fruiting  organs  in  the  form  of  swellings  or  short 
lateral  branches. 

With  a  power  of  about  thirty  to  sixty  diameters  sketch  a  selected 
plant  of   moderate   extent   as   nearly  complete  as  possible  or  else 


FIG.  180. —  Vaucherla  synandra. 

A,  a,  filament  with  archegonia  and  an  theridia  (considerably  magnified);  B,  part 
of  same  much  more  highly  magnified ;  o,  oogonium ;  a,  antheridium ;  C,  a 
later  stage  of  B ;  Z>,  end  of  a  filament  with  a  zoospore,  z,  escaping  (highly 
magnified). 

sketch  a  portion  showing  the  branching  and  a  root-like  portion. 
Note  and  indicate  the  absence  or  presence  and  arrangement  of 
chlorophyll.  Can  Vaucheria  probably  use  carbon  dioxide? 

284.  Reproduction  in  Vaucheria.  —  Make  an  outline  sketch  of 
fruiting  organs,  if  found.  See  if  any  filaments  can  be  found  with 
the  contents  massing  or  escaping  at  the  tips.  In  some  species 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     247 

zoospores  are  formed  in  this  way,  having  their  entire  surface  clothed 
with  cilia.  They  are  the  largest  motile  cells  known.  In  other  spe- 
cies a  portion  of  the  filament  is  separated  and  cut  off  by  a  cell-wall. 
Such  spores  soon  germinate  and  may  be  found  in  various  stages  of 
growth.  They  often  serve  for  propagation  through  several  genera- 
tions before  spores  are  produced  by  fertilization. 

With  a  power  of  about  200  diameters  sketch  a  portion  of  a  fila- 
ment to  show  the  form  and  location  of  chlorophyll.  Sketch  the 
fruiting  organs  in  detail,  if  any  can  be  found.1 

Antheridia  and  oogonia  are  formed  near  together  on  the  same 
filament.  The  antheridium  is  a  cell  forming  the  terminal  portion 
of  a  short  branch,  which  is  rather  slender,  straight  or  curved.  Its 
contents  form  numerous  minute  antherozoids,  each  with  two  cilia. 
The  cilia  can  be  seen  only  with  great  difficulty,  if  at  all,  but  their 
presence  is  indicated  by  their  active  movements. 

The  oogonium  is  a  short,  somewhat  spheroidal  branch  separated 
by  a  cross-partition  at  the  base.  The  cell-wall  becomes  ruptured  at 
the  tip,  allowing  the  entrance  of  the  antherozoids  by  which  it  is 
fertilized.  After  fertilization  a  cell-wall  is  formed  about  the  oosphere, 
and  it  matures  as  an  oospore  and  enters  upon  a  period  of  rest. 

THE    STUDY   OF   NITELLA 

285.  Occurrence. — Nitella  is  a  green  plant  growing  attached  to 
the  bottom  of  ponds  and  streams,  usually  in  shallow  water.     It  is 
not  common  everywhere  but  is  widely  distributed.     Chara  is  similar 
and  may  be  used  as  a  substitute  but  is  more  complicated. 

286.  General   Aspect.  —  With   the    naked   eye    and   a   magnify- 
ing glass  note  the  general  aspect  of  Nitella,  the  length  of  the  stem- 
like  portions,  from  the  root-like  parts  to  the  tip,  the  length  of  some 
of  the  joints  (internodes),  the  arrangement  of  leaf-like  and  branch- 
like  portions. 

287.  Protoplasm.  —  Examine  the  cells  of  stems  or  leaves  under  a 
low  power.     Select  a  vigorous  cell  of  moderate  size  and  examine 

1  Goebel  states  that  the  formation  of  the  fruiting  organs  begins  in  the  even- 
ing, is  completed  the  next  morning,  and  that  fertilization  takes  place  during 
the  day  between  ten  and  four  o'clock. 


248 


FOUNDATIONS   OF   BOTANY 


under  a  power  of  200  or  more  diameters.  Select  the  terminal  cell 
of  the  leaf  if  Chara  is  used.  The  protoplasm  is  nearly  colorless  but 
usually  contains  bodies  which  can  be  seen  moving  in  the  current  of 
protoplasm.  The  protoplasm  will  show 
normal  activity  at  the  temperature  of  a 
comfortable  living  room.  By  focusing,  see 
if  the  current  of  protoplasm  can  be  detected 
moving  in  more  than  one  direction. 

Note  the  form  and  arrangement  of  the 
chlorophyll  and  any  places  lacking  chloro- 
phyll, and  see  if  you  can  tell  whether  the 
arrangement  has  any  relation  to  the  current 
of  protoplasm.  With  a  low  power  trace  the 
course  in  several  cells.  How  many  cells  con- 
stitute each  internode  of  Nitella  1  If  Chara 
is  used,  internodes  will  be  found  to  be 
covered  with  a  layer  of  many  corticating 
cells.  Under  a  high  power  compare  the 
general  structure  of  node  and  internode  and 
see  if  the  attachment  of  leaves  and  branches 
can  be  clearly  determined.  Compare  the  tip 
of  a  leaf  with  the  tip  of  a  stem  or  branch 
if  the  material  permits.  Are  the  fruiting 
organs  produced  on  the  sterns  or  the  leaves  ? 
288.  Antheridia.  —  The  antheridia  are 
globular  bodies,  bearing  male  fertilizing 
cells  and  becoming  red  at  maturity  (Fig. 
182).  Eight  cells  compose  the  outer  wall. 
They  have  radial  lines  indicating  folds  and 
join  one  another  by  irregular  sutures.  Note 
a  round  spot  in  the  middle  of  each  cell 
which  marks  the  point  of  attachment  within 
of  the  stalk  on  which  antherozoid-producing  cells  are  borne. 

289.  Oogonia.  —  The  egg-shaped  fruits,  known  as  oogonia  (Fig. 
182),  are  borne  near  the  antheridia  in  monoecious  species.  Count 
the  number  of  pointed  cells  which  constitute  the  "  crown  "  of  the 
fruit.  Does  each  tip  consist  of  one  or  two  short  cells  ?  Examine 


FIG.  181.  —  End  of  a  Main 
Shoot  of  Chara.  (About 
natural  size.) 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     249 


the  surface  of  the  enveloping  cells  which  enclose  the  spore.  What 
is  their  number  and  form  ?  What  is  their  relation  to  the  cells  form- 
ing the  crown  ?  Focus  so  as  to  see  the  larga  egg-cell  (oosphere  or 
obspore)  which  constitutes  the  center  of  the  fruit.  Can  you  determine 
anything  regarding  its  contents  ? 

Search  for  young  oogonia  and  if  practicable  describe  and  draw 
them  in  several  stages  of  development.  Their  structure  can  be  seen 
much  more  easily  than  that  of  the 
antheridia.  Make  drawings  to  illus- 
trate various  details  of  structure. 

290.  Characeae.  —  Nitella 
and  Char  a  are  the  genera 
composing  the  group  CJiara- 
cece,  a  group  of  green  algse 
differing  widely  from  any 
others.  They  show  in  a  won- 
derful manner  simplicity  of 
cell-structure  with  a  high 
decree  of  organization.  FlG- 182.— Partof  a  Leaf  of  rig.  isi. 

(Considerably  magnified.) 

Scarcely   less    wonderful    are    a,antneridium.  0,0ogonium.  At  the 
the    care  and   precision  with  -   risht  are  a  y°ung  antheridium  and 

archegonium. 

which  botanists  have  worked 

out  their  life  history.  As  a  study  in  evolution  the  Characece 
may  be  considered  as  representing  the  highest  develop- 
ment attained  along  the  line  of  filamentous  green  algse, 
which,  while  preserving  their  algal  characteristics,  are 
comparable  in  a  remarkable  degree  with  moss-  and  fern- 
plants  and  with  seed-plants.  Every  cell  in  the  plant  has 
been  accounted  for  and  is  understood  in  regard  to  origin, 
relationship,  and  function.  With  harmony  of  structure 
throughout,  it  has  organs  comparable  to  root,  stem,  and 
leaf  in  seed-plants,  each  with  characteristic  structure  and 


250 


FOUNDATIONS   OF   BOTANY 


mode  of  growth.  The  stem  has  nodes  and  internodes. 
The  stem  increases  by  the  growth  of  an  apical  cell,  but 
growth  in  length  depends  chiefly  on  the  elongation  of  each 
internodal  cell  instead  of  the  multiplication  of  numerous 
internodal  cells. 


THE   STUDY   OF   ROCKWEED1 

291.    Occurrence.  —  The   common  rockweed  is  abundant  every- 
where on  rocks,  between  high  and  low  tide,  on  the  New  England 
coast  and  southward. 

292.  The  Frond.  —  A  plant  of  rockweed 
consists  mostly  of  a  growth  which  is  some- 
what leaf-like,  but,  in  fact,  stem  and  leaf 
are  not  separately  developed,  and  the  growth 
is  therefore  called  a  thallus.     This  combined 
stem    and    leaf    has    many    flat    leathery 
branches  wThich  are  buoyed  up  in  the  water 
by  air-bladders.     Cut  one  of  the  bladders 
open  and  note  its  form  and  appearance.  Note 
whether  they  occur  singly  or  how  grouped. 
Note  the  prominent  midrib  running  through- 
out the,  middle  of  each  branch.     Examine 
the  swollen  tips  of  some  of  the  branches  and 
note  their  peculiarities.     Sketch  a  portion 
of  a  frond  to  show  the  characteristics  so  far 
noted. 

293.  Reproduction.  —  Cut  across  through 
the  middle  of  one  of  the  swollen  fruiting 
tips.      Note  the  fruiting   papillae    (concep- 
tacles)  as  they  appear  in  this  section,  and 
make  a  simple  sketch  to  show  their  position. 

Select  some  plants  with  brighter  colored 

FIG.  183. -Part  of  Thallus  of   tips  and  some  less  bright,  if  any  difference 
a  Rockweed  (Fucus  platy- 
carpus),  natural  size.    The 

two  uppermost  branchlets        l  Fucus  vesiculosus  is  the  most  available  species, 
are  fertile.  Others  may  be  substituted. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES 


251 


can  be  detected.  After  making  the 
microscopic  examination  which  follows, 
note  what  correspondence  of  structure 
with  color  has  been  observed.  Cut  very 
thin  sections  through  fruiting  tips  from 
different  plants,  keeping  those  from  each 
plant  separate.  Be  sure  that  some  of 
the  cuts  pass  through  the  conceptacle  as 
near  the  middle  as  possible. 

Examine  with  a  power  of  about  sixty 
diameters  sections  from  different  fronds, 
searching  for  one  kind  containing  rather 
large  egg-shaped  cells  and  another  con- 
taining bundles  of  numerous  smaller 
sac-shaped  cells.  With  a  power  of  200 
diameters  study  the  details  of  the  sec- 
tions. Note  the  character  of  the  cells 
forming  the  surface  of  the  frond,  those 
of  the  inner  structure,  and  those  limit- 
ing the  cavity  of  the  conceptacle.  In  a 
conceptacle  cut  through  the  middle  note 
the  form  of  the  orifice.  Examine  the 
slender  hairs  or  filaments  (paraphyses) 
which,  arising  at  right  angles,  line  the 
walls  of  the  conceptacle. 

294.  06'gonia  and  Antheridia.  —  In 
conceptacles  containing  egg-shaped  cells 
(oSgonia)  note  the  form, 
mode  of  attachment  (ses- 
sile or  stalked),  and  dif- 
ferent stages  of  develop- 
ment. At  maturity  the 
contents  are  divided, 
forming  eight  oospheres; 
but  not  all  can  be  seen 
at  once,  some  being  be- 
neath  the  others. 


FIG.  184.— Rockweed  (Fucus). 
A,  antheridia  borne  on  branch- 
ing hairs,  x  160 ;  £,  anthero- 
zoids  from  same,  x  330. 


-  185.  -Rockweed  (Fucus). 


x  160  ;  B,  an  obsphere,  escaped,  surrounded  by  an 


therozoids,  x  ieo. 


252 


FOUNDATIONS   OF  BOTANY 


In  conceptacles  of  the  other  kind  examine  the  numerous  small 
sac-shaped  cells  (antheridia).  At  maturity  the  contents  of  each 
divide  to  form  numerous  very  minute  motile  antherozoids,  each  with 
two  delicate  hairs  or  cilia.  Dissect,  by  picking  and  by  friction  under 

cover-glass,  a  bunch  of 
antheridia  and  note 
the  branching  fila- 
ments upon  which 
they  are  borne. 

Make  drawings  to 
illustrate  the  various 
points  of  structure. 

295.  Number  of 
Antherozoids  required 
for  Fertilization.  —The 
bulk  of  an  oosphere 
has  been  estimated 
equal  to  that  of  thirty 
thousand  to  sixty 
thousand  antherozoids, 
but  apparently  an 
oosphere  may  be  fer- 
tilized by  only  one 
antherozoid.  Yet  a 
large  number  swarm 
around  each  oosphere 
after  b  oth  have 
escaped  from  the  con- 
ceptacles, and  often 
their  movements  are 
so  active  as  to  cause  the  rotation  of  the  oosphere.  The  process  of 
fertilization  may  be  discerned  in  fresh  material  by  squeezing 
oospheres  and  antherozoids  from  their  respective  conceptacles  into 
a  drop  of  water  on  a  slide.  In  some  species,  as  Fucus  platycarpus 
(Fig.  186),  antheridia  and  oogonia  are  found  in  the  same 
conceptacle. 


FIG.  186.  — Transverse  Section  of  Conceptacle  of  a 
Rockweed  (Fucus  platycarpus).    (x  about  35.) 

h,  hairs  ;  a,  antheridia ;  o,  oogonia. 


TYPES   OF  CRYPTOGAMS;   THALLOPHYTES  253 


THE    STUDY    OF   NEMALION 

296.  Occurrence.  —  Seven  or  eight  species  of  Nemalion  are  known 
in  the  world,  but  only  one  J  is  widely  diffused,  being  found  in  Europe 
and  on  the  New  England  coast  from  Rhode  Island  northward.     It 
grows   in  salt  water  attached  to  exposed  rocks  at  low-water  mark. 
Nemalion  represents  the  largest  of  the  groups  of  algse,  nearly  all  of 
which  live  in  salt  water  and  have  the  characteristic  color  ;  but  a  few 
live  in  fresh  water. 

297.  Color.  —  Fresh  specimens  or  those  properly  dried  for  the 
herbarium  show  the  color  which  is  characteristic  of  the  great  group 
to    which   Nemalion  belongs.      Dried    specimens  of    "  Irish  moss " 
(Chondrus)  and  many  other  species  furnish  good  illustrations.    There 
are  many  variations  of  shade  and  intensity. 

Place  a  piece  of  a  fresh  or  dried  specimen  of  some  species  in  a 
beaker  of  fresh  water  over  night  or  longer  and  note  the  color  of  the 
solution  and  of  the  treated  specimen.  Treat  another  piece  similarly 
with  alcohol.  A  few  genera  related  to  Nemalion  grow  in  fresh 
water.  What  do  you  infer  regarding  their  color? 

298.  Form    and    General    Character.  —  Examine    specimens    of 
Nemalion  and  note  the  size,  shape,  mode  of  branching,  nature,  or 
consistency  of  their  substance.     Examine  a  fragment  of  the  plant 
with  a  power  of  about  sixty  diameters  and  note  how  the  structure 
differs  from  what  it  appears  to  be  to  the  naked  eye.    Do  cells  appear 
more  densely  packed  or  differently  colored  at  any  points? 

299.  Structure.  —  From  a   small  portion  of   the  plant  cut  thin 
longitudinal  and  transverse  sections  or  pull  it  to  pieces  with  needles 
so  as  to  expose  the  inner  portion.     Place  on  a  slide  under  a  cover- 
glass  in  a  drop  of  water.     With  a  power  of  about  250  diameters  or 
more  examine  the  general  structure  of  the  frond,  as  shown  by  a  slide 
prepared  as  above.     Note  the  central  portion  (axis)  of  the  frond  as 
dissected  out,  consisting  of  long,  slender,  thread-like  cells.    Examine 
and  draw  the  branching  rows  of  cells  which,  radiating  from  the 
axis,  form  the  surrounding  outer  structure  of  the  frond.     Note  the 
tips  of  these  branches  and  look  for  the  fruiting  organs  and  fruit 
(spores). 

1  Neinalion  multifidum. 


254 


FOUNDATIONS   OF   BOTANY 


300.  Organs  for  Repro- 
duction. —  The    fruiting 
organs   are   to   be   sought 
on  the  radiating  branching 
filaments  and  are  usually 
produced   in    great    abun- 
dance during  the  summer. 
Various  stages  of  develop- 
ment may  be  expected  at 
a  given  time.     The  anther- 
ozoids    are    small   spheres 
without  cilia,    non-motile, 
with  a  thin  cell-wall.   Look 
for  cells  in  which  they  are 
formed  (antheridia),  occur- 
ring in  groups  at  the  tips 
of  the  branches.    Compare 
these  with  the  vegetative 
cells. 

301.  Spore -Production. 
— Look  for  spore-producing 
organs  in   various  stages. 
In  the  young  stage  at  the 
time   of    fertilization,    an- 
therozoids,  carried  by  cur- 
rents   of    water,    may    be 
found  adhering.     Note  the 
shape  of  the  tip  (trichogyne) 
and  the  base  (carpogonium), 
and  find  whether  there  is 
any    partition    separating 
them  at  this  stage.     Draw 
or    describe    a    few    later 
stages  in  development,  and 
note    the    arrangement   of 

the  spores  at  maturity.     Are  they  naked  or  enclosed  in  any  sort  of 
envelope  ?     Are  they  arranged  in  masses,  chains,  or  otherwise  ? 


B  C 

FlG.  187.  — Portions  of  Thallus  of  a  Bed  Alga 
(Chantransid).    (Much  magnified.) 

A,  filaments  with  antheridia,  a  ;  B,  young  recep- 
tive hair,  or  trichogyne,  t ;  C  and  D,  successive 
stages  in  the  growth  of  the  clustered  fruit,/. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES 


255 


302.  Other  Florideae.  —  Nemalion  represents  one  of  the  simplest 
modes  of  fruiting  in  the  red  algae.     In  others  there  is  great  variety  in 
structure    and  great  complication  in  the  mode  of  fruiting.     Some 
species  of  Polysiplionia  (or  Dasya)  may  well  be  studied  in  compari- 
son with  Nemalion  and  in  further   illustration  of   this   important 
group.1     Understanding  that  a  siphon,  in  algae,  is  a  row  of  cells,  end 
to  end,  study  the  structure  of  a  plant  of  Poly- 

siphonia  as  illustrating  its  name.  How  many 
siphons  are  there?  Do  the  main  branches 
have  any  other  cells  covering  the  surface  (cor- 
ticating  cells)  ? 

Note  the  tufts  of  repeatedly  forking,  one- 
siphoned  filaments. 

303 .  Fruiting  of  Poly siphonia .  —  The  anther- 
idia  are  to  be  sought  on  the  branching  fila- 
ments just  mentioned.     Note  how  they  differ 
from  those  of  Nemalion.     The  clustered  fruits 


— t 


or  cystocarps  will  be  recognized  as  ovoid- 
globose  or  urn-shaped  bodies  attached 
externally  to  the  frond.  Note  whether 
the  group  of  spores  is  naked  or  otherwise, 
whether  the  spores  are  produced  singly 
or  in  chains  ;  how  attached ;  shape. 

Many  Floridece  have  another  kind  of 
fruiting  bodies,  spores  produced  without 
fertilization,  coordinate  with  the  asexual 
spores  "of  black  mould  (see  Sect.  308). 
In  Floridece  such  spores  are  usually 
found  in  fours  and  are  called  tetraspores. 

Are  tetraspores  usually  found  on  separate  plants  ? 

In  Polysiphonia  the  tetraspores  appear  to  be  formed  in  threes 
(tripartite),  the  fourth  being  underneath  the  three.  When  found, 
describe  their  position  and  arrangement. 

304,  Algae.  —  Diatom,  Oscillatoria,  Pleurococcus,  Spi- 
rogyra,  Vaucheria,  Nitella,  Fucus,  Nemalion,  these  eight 

1  It  is  desirable  also  to  exhibit  fresh  or  pressed  specimens  of  various  genera 
to  show  their  general  aspect. 


A 

FIG. 188. 

A,  spores  of  Nemalion  (greatly 
magnified) ;  £,  portion  of 
thallus  of  a  red  alga,  Lejo- 
lisia,  with  tetraspores,  t. 


256  FOUNDATIONS  OF  BOTANY 

plants  which  we  have  just  studied,  are  types  of  several 
families  of  plants  which  together  make  the  great  group 
called  Algce.  Something  of  its  importance  in  nature  is 
indicated  by  these  facts :  The  number  of  known  species  is 
about  12,000.  In  size,  the  individuals  in  various  species 
range  from  a  single  cell  of  microscopic  dimensions,  as  in 
Pleurococcus,  to  the  giant  kelp  of  California  which  reaches 
a  length  of  more  than  1000  feet.  The  form  ranges  from  a 
simple  spherical  cell  as  in  Pleurococcus  to  an  extensive, 
branching  cell  in  Vauclieria  and  its  allies,  specialized 
organs  in  the  form  of  root,  stem,  leaf,  air-bladder,  and 
fruiting  organs  in  Sargassum,  which  is  an  ally  of  Fucus. 

The  algse  illustrate  a  series  of  modes  of  propagation 
from  simple  division  in  Oscillatoria  to  the  union  of  two 
similar  masses  of  protoplasm  to  form  a  spore  in  Spirogyra, 
the  direct  fertilization  of  a  -germ-cell  by  motile  anthero- 
zoids  in  Vaucheria,  Nitella,  Fucus,  the  indirect  fertilization 
of  fruiting  cells  by  non-motile  antherozoids  in  Nemalion. 
In  allies  of  the  latter  there  are  more  intricate  variations  of 
the  same  mode. 

The  algse  fall  into  five  natural  groups  based  primarily 
on  the  mode  of  fruiting.  In  most  cases  color  is  coordinate 
with  class  arid  may  be  relied  upon  as  a  superficial  guide  in 
grouping  ;  but  there  are  a  few  exceptions,  e.g.,  some  fruit- 
ing like  the  red  group  are,  nevertheless,  green. 

The  nutrition  of  the  brown  and  the  red  algse  is  similar 
to  that  of  the  green  algse,  since  the  brown  or  red  color 
merely  conceals  the  green  of  the  chlorophyll  which  is 
present  in  all  and  enables  them  all  to  take  in  and  decom- 
pose carbon  dioxide.1 

1  See  Murray's  Introduction  to  the  Study  of  Seaweeds,  pp.  4-6.  London, 
1895. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     257 

305.  Classification  of  Types  studied. 

DIATOMACE^E.  Yellowish. 

Diatoms. 
CYAXOPHYCE^E.  Blue-green  or  some  similar  color. 

Oscillatoria. 
CHLOROPHYCE.E.  Green. 

Pleurococcus,  Spirogyra, 

Vaucheria,  Nitella. 
PH^EOPHYCEjE.  Olive. 

Fucus. 
FLORIDE^E.  Red. 

Nemalion. 

Polysiphonia. 

THE  STUDY  OF  BLACK  MOULD  (RHIZOPUS  NIGRICANS) 

306.  Occurrence. — This  mould  maybe  found  in  abundance  on 
decaying  fruits,  such  as  tomatoes,  apples,  peaches,  grapes,  and  cher- 
ries, or  on  decaying  sweet  potatoes  or  squashes.     For  class  study  it 
may  most  conveniently  be  obtained  by  putting  pieces  of  wet  bread 
on  plates  for  a  few  days  under  bell-jars  an<J  leaving  in  a  warm  place 
until  patches  of  the  mould  begin  to  appear. 

307.  Examination   with  the  Magnifying  Glass.  —  Study  some  of 
the  larger  and  more  mature  patches  and  some  of  the  smaller  ones. 
Note  : 

(a)  The  slender,  thread-like  network  with  which  the  surface  of 
the  bread  is  covered.  The  threads  are  known  as  hyphce,  the  entire 
network  is  called  the  mycelium. 

(6)  The  delicate  threads  which  rise  at  intervals  from  the  myce- 
lium and  are  terminated  by  small  globular  objects.  These  little 
spheres  are  spore-cases.  Compare  some  of  the  spore-cases  with 
each  other  and  notice  what  change  of  color  marks  their  coming  to 
maturity. 

308.  Examination  with  the  Microscope.  —  Sketch  a  portion  of  the 
untouched  surface  of  the  mould  as  seen  (opaque)  with  a  two-inch 
objective,  then  compare  with  Fig.  189. 


258 


FOUNDATIONS   OF  BOTANY 


Wet  a  bit  of  the  mould,  first  with  alcohol,  then  with  water. 
Examine  in  water  with  the  half-inch  objective,  and  sketch  a  little  of 
the  mycelium,  some  of  the  spore-cases,  and  the  thread-like  stalks  on 
which  they  are  borne.  Are  these  stalks  and  the  mycelium  filaments 
solid  or  tubular  ?  Are  they  one-celled  or  several-celled  ? 

Mount  some  of  the  mature  spore-cases  in  water,  examine  them 
with  the  highest  obtainable  power,  and  sketch  the  escaping  spores. 


FIG.  189.  —  Unicellular  Mycelium  of  a  Mould  (Mucor  Mucedo),  sprung  from  a 
Single  Spore. 

a,  6,  and  c,  branches  for  the  production  of  spore-cases,  showing  various  stages  of 
maturity.    (Considerably  magnified.) 

Sow  some  of  these  spores  on  the  surface  of  "  hay-tea,"  made  by 
boiling  a  handful  of  hay  in  just  water  enough  to  cover  it  and  then 
straining  through  cloth  or  filtering  through  a  paper  filter.  After 
from  three  to  six  hours  examine  a  drop  from  the  surface  of  the 
liquid  with  a  medium  power  of  the  microscope  (half-inch  objective) 
to  see  how  the  development  of  hyphse  from  the  spores  begins. 
Sketch. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES 


259 


After  about  twenty-four  hours  examine  another  portion  of  the 
mould  from  the  surface  of  the  liquid  and  study  the  more  fully 
developed  mycelium.  Sketch. 

309,  Zygospores. — Besides 
the  spores  just  studied,  zygo- 
spores  are  formed  by  conju- 
gation of  the  hyphae  of  the 
black  moulds.  It  is  not  very 
easy  to  find  these  in  process 
of  formation,  but  the  student 
may  be  able  to  gather  from 
Fig.  190  the  nature  of  the 
process  by  which  they  are 
formed, — a  process  which  can- 
not fail  to  remind  him  of  the 
conjugation  of  pond-scum. 

THE  STUDY  OF  WHEAT 

RUST    (PUCCINIA 

GRAMINIS) 

310.  Occurrence.  —  Wheat 
rust  is  common  on  cultivated 
wheat  and  other  grains,  and 
also  on  many  wild  and  culti- 
vated forage  grasses.  In  fact, 
this  or  similar  rusts  occur  on 
a  very  large  number  of  grasses, 
and  many  species  of  such  rusts 
are  recognized.  A  rust  may 


FlG.  190.  —  Formation  of  Zygospores  in  a 

Mould  (Mucor  Mucedo) . 
1,  threads  in  contact  previous  to  conjuga- 
tion ;  2,  cutting  off  of  the  conjugating 
cells,  a,  from  the  threads,  6 ;  3,  a  later 
stage  of  the  process  ;  4,  ripe  zygospore  ;  5, 
germination  of  a  zygospore  and  formation 
of  a  spore-case.  (1-4  magnified  225  diam- 
eters, 5  magnified  about  60  diameters.) 


have  one,  two,  or  three  kinds 
of  spores,  and  when  three  occur  one  is  known  as  the  cluster-cup  stage 
and  the  others  as  red  rust  and  black  rust,  according  to  the  usual 
approximate  color  of  the  spores.  The  rust  called  Puccinia  graminis 
growing  on  wheat  has  its  cluster-cup  stage  on  the  leaves  of  barberry 
in  June.  The  spores  from  the  cluster-cups  are  carried  by  the  wind 
to  the  wheat,  where  they  germinate  and  in  a  few  days  produce  the 


260 


FOUNDATIONS   OF   BOTANY 


red  rust.     A  little  later  the  black  spores  appear,  produced  from  the 
same  mycelium.     This  growth  is  chiefly  upon  the  stems  and  sheaths. 


A  B 

FIG.  191.  —  Spore-Formation  in  Potato-Blight  (Phytophthora  infestans). 

A,  a  well-developed  group  of  stalks,  proceeding  from  a  mass  of  mycelium  inside 
the  leaf  and  escaping  through  a  stoma ;  B,  a  young,  unbranched  stalk,  h, 
hyphse  of  mycelium  ;  o,  stoma ;  s,  spore.  (Both  figures  greatly  magnified,  B 
more  than  A.} 

311.  Cluster-Cup  Stage.  —  Note  with  the  naked  £ye  and  with  a 
magnifying  glass  the  appearance  of  the  cluster-cups  upon  the  bar- 
berry leaf.  Fresh  specimens  should  be  used,  if  available.  Note 
whether  the  leaf  is  changed  in  form  or  color  in  any  part  occupied 
by  the  fungus.  Note  the  number  of  cups  in  a  cluster,  the  position 
on  the  leaf  (which  surface?),  the  form  and  size,  especially  the  height. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     261 

Are  they  straight  or  curved  ?  Describe  the  margin  of  the  cup,  the 
color  without,  and  the  color  of  the  contents. 

With  a  power  of  200  diameters  or  more  examine  some  of  th.3 
cells  composing  the  cup  and  note  the  form,  color,  and  nature  of  the 
surface.  Draw.  With  the  point  of  a  needle  or  knife  pick  out  a 
bit  of  the  contents  of  the  cup  and  examine  as  above.  Note  the 
characters  as  before  and  compare  in  detail  with  the  cells  of  the  cup. 
The  cells  within  the  cup  are  the  spores.  Can  you  tell  how  they  are 
attached  ? 

A  thin  section  through  the  cup  will  show  the  mode  of  attachment 
and  the  relation  of  the  spores  to  the  cup. 

312.  Examination  of  Red  and  Black  Rust. — Under  the  magnify- 
ing glass  examine  the  eruptions  of  spores  (son)  on.  the  wheat  plant, 
some  of  red  spores  and  some  of  black  spores.  The  red  spores  are 
faded  in  dried  specimens.  Note  the  approximate  size  and  shape 
and  any  other  peculiarities.  Prepare  slides  of  each  kind  of  spores 
and  see  if  both  can  be  found  in  one  sorus.  The  spores  may  be 
taken  from  the  host-plant  on  the  point  of  a  knife  by  picking  rather 
deeply  down .  into  the  sorus.  Place  the  small  quantity  of  spores  so 


FIG.  192.  — A  Cluster-Cup  of  Anemone  Rust  (Puccinia  fused),    (x  120.) 
s,  chains  of  spores  ;  p,  the  covering  or  peridium  of  the  cup  ;  h,  hyphae. 

obtained  in  a  drop  of  water  on  a  slide,  spread  with  dissecting  needles 
and  cover.     Examine  under  a  power  of  200  or  more  diameters. 

The  red  spores  (uredospores}  have  each  a  stalk  from  which  they 
easily  fall.     They  may  be  seen  attached  to  their  stalks  if  properly 


262 


FOUNDATIONS   OF  BOTANY 


U 


u 


prepared  cross-sections  through  the  sorus  are  available,  especially  if 
the  material  is  fresh.  Examine  the  spores  and  note  the  shape,  color, 
and  surface.  If  the  spores  are  shrunken,  a  drop  of  potash  solution 
will  restore  the  natural  plumpness.  Draw.  Spore-measurements  are 
important  in  determining  species.  The  uredospores  of  Puccinia 
graminis  may  be  distinguished  from  those  of  other  species  common 

on  grasses  by  the  greater  proportionate 
length. 

The  structure  of  the  black  spores 
(teleutospores)  can  be  made  out  with- 
out difficulty.  Some  should  be  found 
attached  at  the  base.  Note  the  parts 
and  the  differences  in  color  in  different 
portions.  Make  careful  drawings  to 
show  shape  and  structure  of  both  kinds 
of  spores. 

Boil  a  portion  of  a  rust-injured  plant 
in  potash  solution,  pick  it  to  pieces  on 
a  slide  under  the  magnifier  or  dissect- 
ing microscope,  use  a  cover-glass  and 
examine  the  preparation  for  mycelium, 
using  a  high  power. 

313.  Cultivation  on  a  Host-Plant.  — 
If  practicable,  find  some  wheat  or  grass 
which  has  remained  over  winter  with 
the  black  rust  upon  it.  Tie  a  bunch 
of  this  to  a  barberry  bush  while  the 
leaves  are  young  or  unexpanded.  When 
the  time  arrives  for  the  appearance  of 
the  cluster-cups,  note  whether  they  are  any  more  abundant  on  this 
bush  than  on  others.  Are  you  sure  that  the  rust  you  have  is  the 
one  to  which  the  barberry  cluster-cups  belong  ? 


FIG.  193.  — A  Group  of  Spores 
of  Wheat  Rust  (Puccinia 
graminis).    (x  about  440.) 
u,  u,  uredospores  ;  t,  a  teleu- 
tospore. 


TYPES   OF   CRYPTOGAMS;   THALLOPHYTES  263 


THE   STUDY   OF   MICROSPH^RA 

314.  Occurrence.  —  Species   of    Microsphcera    and    allied    forms 
occur  in  late  summer  and  fall  on  leaves  of  various  herbaceous  and 
woody  plants.     The  growth  is  confined  to  the  surfaces  of  the  leaf 
(upper,   lower,   or  both).     Among  the  most  available  species  are 
those  which  grow  upon  lilac,  oak,  grape,  cherry,  willow,  and  wild 
plants  of  the  sunflower  family.     Some  species  are  known  to  occur 
on  only  one  host-plant,  others  occur  on  several  or  a  large  number, 
and  the  host-plants  may  belong  to  one  or  more  than  one  family. 

Besides  Microsphcera  there  are  about  five  other  genera,  any  of 
which  may  be  substituted  or  studied  comparatively.  They  are  dis- 
tinguished by  the  form  of  the  appendages,  together  with  the  number 
of  spore-sacs  (asci)  in  each  sac-receptacle  or  perithecium. 

The  species  of  fungi  which  Microsphcera  represents  are  called 
powdery  mildews. 

With  naked  eye  and  magnifying  glass  examine  the  surface  of  a 
leaf  bearing  powdery  mildew.  Note  which  surface  and  what  portion 
of  the  surface  is  occupied  by  the  fungus,  whether  the  occupied  area 
is  restricted  or  not,  the  color,  and  any  other  characters. 

315.  Examination  with  the  Microscope.  —  Place  a  small  drop  of 
water  on  the  leaf  where  the  fungus  occurs,  if  possible  where  dark- 
colored  specks  occur  among  the  mycelium.     Pick  from  the  leaf  a 
portion  of  the  fungus  loosened  by  the  water  and  place  with  a  drop 
of  water  on  a  slide.     Place  a  cover-glass  over  it.     Examine  under 
a  power  of  about  fifty  diameters.     The  dark-colored  specks  will  be 
seen  as  somewhat  spherical  bodies  (perithecia).     Note  their  structure 
and  color  and  their  appendages.     Have  the  perithecia  any  regular 
way  of  opening?     Note  the  length  of  the  appendages  as  compared 
with  the  diameter  of  the  perithecia ;  also  note  the  form  of  the  tips 
and  of  the  base,  the  color  and  any  variation  of  color  in  different 
parts  of  the  appendages.     Keep  the  left  hand  on  the  focusing  screw, 
and  with  the  needle  in  the  right  hand  press  with  gentle  but  varying 
stress  upon  the  cover-glass  to  rupture  the  perithecia.     Even  with 
great  care  broken  cover-glasses  may  result,  but  this  pressure  should 
force  out  the  contents  of  the  perithecia.      Another  method  is  to 
remove  the  slide  from  the  microscope  and,  with  a  pencil  rubber 


264 


FOUNDATIONS   OF  BOTANY 


applied  to  the  cover-glass,  rupture  the  perithecia  by  gentle  grinding 
between  the  cover  and  slide.  Note  the  number  and  form,  of  the 
spore-sacs  (asci)  expelled  from  each  of  several  perithecia.  Examine 

under  a  power  of  about  200  diam- 
eters and  count  the  number  of  spores 
in  the  asci.  Gentle  pressure  may 
make  them  more  distinctly  visible. 
Make  drawings  to  illustrate  the 
structural  characters  observed. 


THE  STUDY  OF  AGARICUS 

316.  Occurrence.  —  The  common 
mushroom,  A garicus  campestris, 
grows  in  open  fields  and  pastures 
in  the  United  States  and  Europe. 
It  is  the  mushroom  most  extensively 
cultivated  for   market,  and  if   not 
found  in  the  field  it  may  be  raised 
from  "spawn"  (mycelium),  put  up 
in  the  shape  of  bricks,  and  sold  by 
seedsmen  in  the  large  cities.    Those 
who  make  a  specialty  of  selling  it 
furnish  directions  for  culture  free. 
A  moderately  warm  cellar  or  base- 
ment   makes    an    excellent  winter 
garden  for  mushrooms. 

317.  Structure    of    Mycelium. — 
Examine   some    of    the   spawn,    or 
mycelium,  with  the  magnifying  glass 
and  the  low  power  of  the  microscope, 
and  with  a  power  of  200  diameters 
or    more    examine    the    individual 

hyphse  which  compose  it.  Are  the  hyphse  united  in  cord-like  strands 
or  otherwise,  or  are  they  entirely  separate  ?  Look  for  cross-partitions 
in  the  hyphse.  Is  there  any  peculiar  structure  to  be  found  at  these 
places  ?  Are  the  cross-partitions  near  together  or  widely  separated  ? 


FIG.  194.  —  A  Mushroom  (Agaricus 

melleus). 
my,   mycelium ;    c,   c" ,   c",   young 

"  buttons  "  ;  st,  stipe  or  stalk ;  r, 

ring;  g,  gills. 


TYPES  OF  CKYPTOGAMS;  THALLOPHYTES 


265 


hym 


J 


318.  The  Spore-Plant.  —  Search  for  indications  of  fruiting,  and 
note  the  appearance  of  the  "  button  mushrooms  "  in  all  available 
stages.  Draw.  See  if  at  any  stage  up  to  maturity  an  outer  envelope 
of  tissue  (volvcf)  can  be  found  enclosing  the  entire  fruiting  body. 
If  such  be  present,  what  becomes  of  it  at  maturity?  If  material  is 
available,  compare  the  species  of  Amanita  (poisonous)  in  regard  to  this. 

Examine  specimens  in  which  the  cap  is  expanding  and  see  if 
there  is  another  tissue  forming  a  veil  covering  the  under  surface  of 
the  cap.  If  such  be  pres- 
ent, how  is  it  attached 
and  what  becomes  of  it? 

Take  a  fresh,  well- 
expanded  mushroom  or 
toadstool.  Remove  the 
stalk,  or  stipe,  close  under 
the  cap,  or  pileus,  and  lay 
the  latter,  gills  down,  on 
a  piece  of  paper.  Let  it 
remain  undisturbed  for  a 
few  hours,  or  over  night, 
so  that  the  spores  may 
fall  upon  the  paper.  Note 


FIG.  195.  —  Portions  of  Gills  of 

a  Fungus  (Agaricus). 
A,  slightly  magnified;   J3,  one 
of  the  parts  of  A ,  more  mag- 
nified,   hym,  hymenium;   h, 
central  layer. 


carefully  their  color,  also 
the  form  in  which  they 
are  arranged  on  the  paper.  What  determines  this  form  ?  Examine 
some  of  the  spores  under  the  highest  available  power  of  the  micro- 
scope. Measure  and  draw. 

Describe  the  stipe.  Is  it  a  hollow  tube  or  solid  ?  Does  it  taper  ? 
Note  length,  diameter,  color. 

Describe  the  cap,  or  pileus,  in  regard  to  diameter,  thickness,  nature 
and  color  of  the  upper  surface,  also  color  below. 

Examine  the  plates,  or  gills,  which  compose  the  under  portion  of 
the  pileus.  Cut  a  complete  pileus  and  stipe,  through  the  center,  and 
draw  an  outline  to  show  the  shape,  noting  particularly  how  the  gills 
are  attached.  What  is  the  color  of  the  gills? 

319,  Origin  of  Spores.  —  Make  a  cross-section  of  one  of  the  gills, 
and  with  a  magnifying  power  of  about  200  diameters  examine  the 


266 


FOUNDATIONS   OF   BOTANY 


C 


fruiting  cells  (basidid)  which  project  at  right  angles  to  the  gill  and 
bear  the  spores.  At  how  many  points  (sterigmata)  on  each  basidium 
are  spores  attached?  Draw  a  basidium,  preferably  one  from  which 
the  spores  have  not  yet  fallen. 

THE  STUDY  OF  YEAST  (SACCHAROMYCES  CEREVISLE) 

320.  Growth  of  Yeast  in  Dilute  Syrup.  —  Mix  about  an  eighth  of 
a  cake  of  compressed  yeast  with  about  a  teaspoonful  of  water  and 
stir  until  a  smooth,  thin  mixture  is  formed.  Add -this  to  about  half 

a  pint  of  water  in  which  a  table- 
spoonful  of  molasses  has  been 
dissolved.  Place  this  mixture  in 
a  wide-mouthed  bottle  which  holds 
one  or  one  and  a  half  pints,  stop- 
pel-  very  loosely  l  and  set  aside  for 
from  twelve  to  twenty-four  hours 
in  a  place  in  which  the  temper- 
ature will  be  from  70  to  90  degrees. 
Watch  the  liquid  meantime  and 
note  : 

(a)  The  rise  of  bubbles  of  gas 
in  the  liquid. 

(&)  The  increasing  muddiness 
of  the  liquid,  a  considerable  sedi- 
ment usually  collecting  at  the  end 
of  the  time  mentioned. 

(c)  The  effect  of  cooling  off  the 
contents  of  the  bottle  by  immers- 
ing it  in  broken  ice  if  convenient, 
or,  if  this  is  not  practicable,  by 
standing  it  for  half  an  hour  in  a  pail  of  the  coldest  water  obtainable, 
or  leaving  it  for  an  hour  in  a  refrigerator,  afterwards  warming  the 
liquid  again. 

(d)  The  effect  of  shutting  out  light  from  the  contents  of  the 
bottle  by  covering  it  with  a  tight  box  or  large  tin  can. 

1  If  the  cork  is  crowded  into  the  neck  with  any  considerable  force,  pressure 
of  gas  and  an  explosion  may  result. 


FIG.  196.  —  Part  of  the  Preceding  Figure, 
(x  about  300.) 

C,  layer  of  cells  immediately  under  the 
hymenium  ;  s,  s',  s",  three  successive 
stages  in  growth  of  spores. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     267 

(e)  The  result  of  filling  a  test-tube  or  a  very  small  bottle  with 
some  of  the  syrup-and-yeast  mixture,  from  which  gas-bubbles  are 
freely  rising,  and  immersing  the  small  bottle  up  to  the  top  of  the 
neck  for  fifteen  minutes  in  boiling  water.  Allow  this  bottle  to 
stand  in  a  warm  place  for  some  hours  after  the  exposure  to  hot 
water.  What  has  happened  to  the  yeast-plants? 

(/)  The  behavior  of  a  lighted  match  lowered  into  the  air  space 
above  the  liquid  in  the  large  bottle,  after  the  latter  has  been  standing 
undisturbed  in  a  warm  place  for  an  hour  or  more. 

(<7)  The  smell  of  the  liquid  and  its  taste. 

321.  Microscopical  Examination  of  the  Sediment.1  —  Using  a  very 
slender  glass  tube  as  a  pipette,  take  up  a  drop  or  two  of  the  liquid 
and  the  upper  layer  of  the  sediment  and  place  on  a  glass  slide,  cover 
with  a  very  thin  cover-glass  and  examine  with  the  highest  power 
that  the  microscope  affords. 

Note: 

(a)  The  general  shape  of  the  cells. 

(6)  Their  granular  contents. 

(c)  The  clear  spot,  or  vacuole,  seen  in  many  of  the  cells. 

Sketch  some  of  the  groups  and  compare  the  sketches  with 
Fig.  197. 

Run  in  a  little  iodine  solution  under  one  edge  of  the  cover-glass, 
at  the  same  time  touching  a  bit  of  blotting  paper  to  the  opposite 
edge,  and  notice  the  color  of  the  stained  cells.  Do  they  contain  starch  ? 

Place  some  vigorously  growing  yeast  on  a  slide  under  a  cover- 
glass  and  run  in  a  little  eosin  solution  or  magenta  solution.  Note 
the  proportion  of  cells  which  stain  at  first  and  the  time  required  for 
others  to  stain.  Repeat  with  yeast  which  has  been  placed  in  a  slen- 
der test-tube  and  held  for  two  or  three  minutes  in  a  cup  of  boiling 
water. 

With  a  very  small  cover-glass,  not  more  than  three-eighths  of  an 
inch  in  diameter,  it  may  be  found  possible  by  laying  a  few  bits  of 
blotting  paper  or  cardboard  on  the  cover-glass  and  pressing  it  against 
the  slide  to  burst  some  of  the  stained  cells  and  thus  show  their  thin, 
colorless  cell-walls  and  their  semi-fluid  contents,  protoplasm,  nearly 
colorless  in  its  natural  condition  but  now  stained  by  the  iodine. 
1  See  Huxley  and  Martin's  Biology,  under  Torula. 


268 


FOUNDATIONS   OF  BOTANY 


EXPERIMENT  XXXIX 

Can  Yeast  grow  in  Pure  Water  or  in  Pure  Syrup  ?  —  Put  a  bit  of 

compressed  yeast  of  about  the  size  of  a  grain  of  wheat  in  about  four 
fluid  ounces  of  distilled  water,  and  another  bit  of  about  the  same  size 
in  four  fluid  ounces  of  10  per  cent  solution  of  rock  candy  in  distilled 
water ;  place  both  preparations  in  a  warm  place,  allow  to  remain  for 
twenty-four  hours,  and  examine  for  evidence  of  the  growth  of  the 
yeast  added  to  each. 

322.  Size,  Form,  and  Structure  of  the  Yeast-Cell.  —  The  student 
has  discovered  by  his  own  observations  with  the  microscope  that  the 
yeast-cell  is  a  very  minute  object,  —  much  smaller  than  most  of  the 
vegetable  cells  which  he  >has  hitherto  examined.     The  average  diam- 
eter of  a  yeast-cell  is  about  -g^1^ 
of  an  inch,  but  they  vary  greatly 
both  ways  from  the  average  size. 

The  general  form  of  most  of 
the  cells  of  ordinary  yeast  is  some- 
what egg-shaped.  The  structure 
is  extremely  simple,  consisting  of 
a  thin  cell-wall,  which  is  wholly 
destitute  of  markings,  and  a  more 
or  less  granular  semi-fluid  proto- 
plasm, sometimes  containing  a 
portion  of  clearer  liquid,  the  vacu- 
ole,  well  shown  in  the  larger  cells 
of  Fig.  197.1 

323.  Substances  which  compose  the  Yeast-Cell.  —  The  cell-wall  is 
composed   mostly   of  cellulose;  the   protoplasm   consists  largely  of 
water,  together  with  considerable  portions  of  a  proteid  substance,2 

1  This  is  not  the  ordinary  commercial  yeast. 

2  It  may  be  found  troublesome  to  apply  tests  to  the  yeast-cell  on  the  slide, 
under  the  cover-glass.     Testing  a  yeast  cake  is  not  of  much  value,  unless  it 
may  be  assumed  that  compressed  yeast  contains  little  foreign  matter  and  con- 
sists mostly  of  yeast-cells.     Still  the  test  is  worth  making.    Millon's  reagent 
does  not  work  well,  but  the  red  or  maroon  color  which  constitutes  a  good  test 
for  proteids  is  readily  obtained  by  mixing  a  teaspoonful  of  granulated  sugar 
with  enough  strong  sulphuric  acid  to  barely  moisten  the  sugar  throughout, 

-and  then,  as  quickly  as  possible,  mixing  a  bit  of  yeast  cake  with  the  acid  and 


FIG.  197.  —  Yeast  (Saccliaromyces  ellip- 
soideus)  budding  actively. 

A,  a  single  cell ;  B,  group  of  two  budding 
cells  ;  C,  a  large  group  ;  b,  buds. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     269 

some  fat,  and  very  minute  portions  of  sulphur,  phosphorus,  potash, 
magnesia,  and  lime.  It  is  destitute  of  chlorophyll,  as  would  be 
inferred  from  its  lack  of  green  color,  and  contains  no  starch. 

324.  Food  of  the  Yeast-Cell ;  Fermentation.  —  The  diluted  molasses 
in  which  the  yeast  was  grown  in  Exp.  XXXIX  contained  all  the 
mineral  substances  mentioned  in  Sect.  323,  together  with  sugar, 
proteid  materials,  and  water.     The  addition  of  a  little  nitrate  of 
ammonium  would  probably  have  aided  the  growth  of  the  yeast  in 
this  experiment,  by  supplying  more  abundantly  the  elements  out 
of  which  the  yeast  constructs  its  proteid  cell-contents.     A  great  deal 
of  sugar  disappears  during  the  growth  of  the  yeast.1     Most  of  the 
sugar  destroyed  is  changed  into  carbon  dioxide  (which  the  student 
saw  rising  through  the  liquid  in  bubbles)  and  alcohol,  which  can 
be   separated  from    the    liquid  by   simple    means.      The    process 
of  breaking  up  weak   syrup   into   carbon  dioxide   and  alcohol  by 
aid  of  yeast  is  one  kind  of  •  fermentation ;  it  is  of  great  practical 
importance  in  bread-making  and  in  the  manufacture  of  alcohol. 
Since  grape  juice,  sweet  cider,  molasses   and  water,   and   similar 
liquids,  when  merely  exposed  to  the  air  soon  begin  to  ferment  and 
are  then  found  to  contain  growing  yeast,  it  is  concluded  that  dried 
yeast-cells,    in  the  form  of   dust,    must  be  everywhere  present  in 
ordinary  air. 

325.  Yeast  a  Plant;    a  Saprophyte.  —  The   yeast-cell   is   known 
to  be  a  plant,  and  not  an  animal,  from  the  fact  of  its  producing 
a  coating  of   cellulose  around  its  protoplasmic  contents  and  from 
the  fact  that  it  can  produce  proteids  out  of  substances  from  which 
animals  could  not  produce  them.2 

On  the  other  hand,  yeast  cannot  live  wholly  on  carbon  dioxide, 
nitrates,  water,  and  other  mineral  substances,  as  ordinary  green 
plants  can.  It  gives  oif  no  oxygen,  but  only  carbonic  acid  gas,  and 
is  therefore  to  be  classed  with  the  saprophytes,  like  the  Indian  pipe, 
among  flowering  plants  (Sect.  180). 

sugar.  A  comparative  experiment  may  be  made  at  the  same  time  with  some 
other  familiar  proteid  substance,  e.g.,  wheat-germ  meal. 

1  The  sugar  contained  in  molasses  is  partly  cane  sugar  and  partly  grape 
sugar.     Only  the   latter  is  detected  by  the  addition  of  Fehling's  solution. 
Both  kinds  are  destroyed  during  the  process  of  fermentation. 

2  For  example,  tartrate  of  ammonia. 


270  FOUNDATIONS   OF   BOTANY 

326.  Multiplication  of  Yeast.  —  It  is  worth  while  to  notice  the 
fact  that  yeast  is  one  of  the  few  cryptogams  which  have  for  ages 
been  largely  cultivated  for  economic  purposes.     Very  recently  yeast 
producing  has  become  a  definite  art,  and  the  cakes  of  compressed 
yeast   so  commonly  sold  afford  only  one   instance    of  the    success 
that  has  been  attained  in  this  process.     While  yeast-cells  are  under 
favorable  conditions  for   growth,  they   multiply  with   very   great 
rapidity.     Little  protrusions   are  formed   at   some    portion  of  the 
cell-wall,  as  the  thumb  of  a  mitten  might  be  formed  by  a  gradual 
outgrowth  from  the  main  portion.     Soon  a  partition  of  cellulose 
is  constructed,  which  shuts  off  the  newly  formed  outgrowth,  making 
it  into  a  separate  cell,  and  this  in  turn  may  give  rise  to  others, 
while  meantime  the  original  cell  may  have  thrown  out  other  off- 
shoots.    The  whole  process  is  called  reproduction  ~by  budding.     It  is 
often  possible  to  trace  at  a  glance  the  history  of  a  group  of  cells, 
the  oldest  and  largest  cell  being  somewhere  near  the  middle  of  the 
group  and  the  youngest  and  smallest  members  being  situated  around 
the  outside.     Less  frequently  the  mode  of  reproduction  is  by  means 
of  spores,  new  cells  (usually  four  in  number),  formed  inside  one  of 
the  older  cells  (ascus~).     At  length  the  old  cell-wall  bursts,  and  the 
spores  are  set  free,  to  begin  an  independent  existence  of  their  own. 

In  examining  the  yeast-cell  the  student  has  been  making  the 
acquaintance  of  plant  life  reduced  almost  to  its  lowest  terms.  The 
very  simplest  plants  consist,  like  the  slime  moulds,  of  a  speck  of 
jelly-like  protoplasm.  Yeast  is  more  complex,  from  the  fact  that  its 
protoplasm  is  surrounded  by  an  envelope  of  cellulose,  the  cell-wall. 

THE   STUDY   OF   PHYSCIA 

327.  Occurrence.  —  Physcia  is  one  of  the  commonest  lichens.     It 
grows  attached  to  the  bark  of  various  trees. 

328.  The   Thallus.  —  Physcia  consists  chiefly  of  an  irregularly 
expanded  growth  somewhat  leaf-like  in  texture.     It  is  best  to  be  wet 
for  study.     Is  it  separable  from  the  bark  to  which  it  is  attached  or 
is  it  combined  with  it  (incrusted)  ?    Describe  the  general  outline  of 
the  margin,  the  general  color,  and  any  special  variations  of  color 
above,  also  below.     How  is  the  thallus  attached  to  the  bark  ? 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES 


271 


329.  The  Fruit.  —  Look  for  small  lance-shaped  disks  seated  upon 
the  thallus.  Note  the  approximate  sizes  and  color  within  and 
without.  These  disks  are  called  apothecia.  Note  the  very  minute 
black  specks  (spermogones)  which  are  scattered  in  the  surface  of 
the  thallus.  Pick  one  from  the  thallus,  with  as  little  of  the  thallus 
as  possible,  and  examine  under  high  power.  It  may  be  macerated 
in  a  drop  of  potash  solution  and  crushed  under  the  cover-glass.  If 
the  contents  are  not  easily 
denned,  they  may  then  be 
made  more  opaque  by  a  drop 
of  acetic  acid  or  a  stain.  The 
minute  colorless  bodies  con- 
tained in  the  spermogones  are 


FIG.  198.  —  A  Lichen  (Xanthoria). 
(Natural  size.) 


FIG.  199.  — A  Lichen  (Usnea). 
(Natural  size.) 


called  spermatia.  Their  office  in  Physcia  is  obscure,  but  in  a  few 
lichens  they  are  thought  to  unite  with  a  trichogyne  cell,  as  in  the  red 
algae.1  Note  the  minute,  powdery  masses  (soredia)  on  the  surface 
of  the  thallus.  Macerate  if  necessary  under  the  cover-glass  and 
examine  under  a  high  power.  Compare  with  the  structure  of  the 
thallus  as  seen  in  cross-section.  (See  next  paragraph.)  These  soredia 
easily  become  detached  and  develop  into  new  plants. 

Prepare  for  sectioning  by  imbedding  a  small  portion  of  the 
thallus  with  an  apothecium  in  a  piece  of  pith  or  by  any  suitable 
device  for  sectioning,  and  cut  thin  sections  of  thallus  and  fruit. 

1  This,  however,  is  doubtful.  See  Strasburger,  Noll,  Schenk,  and 
Schimper's  Text-Book  of  Botany,  p.  380. 


272 


FOUNDATIONS   OF  BOTANY 


330.  Examination  of  the  Thallus.  —  The  thallus  of  Physcia  as  seen 
in  cross-section  will  be  found  to  consist  of  four  layers,  the  upper 
cortical,  gonidial,  medullary,  and  the  lower  cortical.  The  cortical 
layers  will  be  seen  to  serve  for  protection,  answering  the  purpose  of 
an  epidermis  or  bark.  The  cells  which  compose  them  make  what 
is  called  a  false  parenchyma, — resembling  parenchyma  in  form  but 

as  to  origin  being  trans- 
formed fungal  hyphse. 
Note  the  form  of  the 
hyphse  composing  the 
medullary  layer.     Are 
there    any   cross-parti- 
tions?    Do  any  cells 
appear  circular,  and  if 
so,  what  is  the  explana- 
tion?    The  upper  por- 
tion  of  the  cortical 
layer,  having  green 
cells   intermixed,    con- 
stitutes the  gonidial 
layer.   Why  should  the 
green   cells   be  at  the 
upper  part  of  the  med- 
ullary layer?    Can  you 
detect  any  connection 
between  the  green  cells 
and  the  hyphse  ?      Do 
these    green    cells    re- 
semble  any  cells  pre- 
viously studied  ? 
Make  a  diagram  to  show  the  structure  of  the  thallus. 
What  arrangement  of  layers  would  you  expect  to  find  in  a  lichen 
thallus,  upright  or  suspended  ?     Compare  the  arrangement  in  the 
fruit-body  (apothecium),  describe,  and  sketch.     How  does  the  layer 
of  cells  beneath  the  spore-sacs  resemble  the  cortical  layer  ?    All  but 
these  two  layers  maybe  considered  as  part  of  the  thallus.     To  make 
out  the  details  of  the  fruit,  the  section  must  be  very  thin. 


FIG.  200.  — Transverse  Section  through  Thallus 
of  a  Lichen  (Stictafullginosa).    (x  500.) 

c,  cortical  or  spider mal  layer  ;  g,  gonidia  ;  h,  hyphse. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     273 

Examine  the  spore-sacs  (asci)  and  look  for  spores  in  different  stages 
of  formation.  How  many  spores  are  found  in  each  ascus  ?  What  other 
bodies  occur  among  the  asci?  Draw  these,  also  asci  and  spores. 

331,  Lichens.  —  Lichens  were  formerly  supposed  to  be 
a  distinct  class  of  plants,  and  it  is  only  about  thirty  years 
since  their  real  nature  began  to  be  understood.  A  lichen 
is  now  known  to  be  a  combination  of  two  plants.  The 
green  cells,  called  the  gonidia,  belong  to  some  species  of 
alga,  and  the  remainder,  the  larger  portion  of  the  growth, 
is  a  fungus  parasitic  upon  that  alga.  The  groups  of 
lichens  correspond  in  structure  to  certain  groups  of  fungi, 
but  the  genera  are  sufficiently  distinct  so  that  lichens  are 
best  considered  by  themselves  for  purposes  of  study  and 
classification. 

The  relation  of  the  fungus  and  its  algal  host  is  not 
that  of  destructive  parasitism,  but  rather  a  mutual  rela- 
tion (symbiosis)  in  which  both  fungus  and  alga  may  have 
a  vigorous  growth.  The  relationship  has  been  investi- 
gated in  various  ways,  and  it  has  been  found  that,  while 
the  alga  may  grow  independent  of  the  fungus,  the  germi- 
nating fungus  spores  can  grow  only  to  a  limited  extent  if 
deprived  of  the  algal  host;  but  if  supplied  naturally  or 
artificially  with  the  proper  alga  they  make  a  normal 
growth. 

The  same  alga  may  serve  as  gonidia  to  a  number  of 
lichens,  often  of  very  different  form,  and  while  the  num- 
ber of  lichens  reaches  into  the  thousands,  the  number  of 
algae  known  to  serve  as  gonidia  is  quite  small. 

Lichens  are  widely  distributed  in  all  zones  but  flourish 
particularly  in  northern  regions  where  other  vegetation  is 
scanty.  Some  were  formerly  important  as  sources  of 


274  FOUNDATIONS   OF  BOTANY 

dyes.  "Iceland  moss"  is  a  lichen  used  for  food,  and  a 
finely  branching  form,  growing  in  extensive  mats  on  the 
soil,  serves  as  food  for  the  reindeer  and  is  known  as 
"  reindeer  moss." 

Most  lichens  grow  on  the  bark  of  trees,  on  rocks,  or  soil 
where  they  have  little  moisture  except  during  rainfall, 
but  some  grow  where  they  are  constantly  wet.  Some  of 
the  latter  are  gelatinous.  Most  of  the  conspicuous  lichens 
are  foliaceous  or  else  have  a  thallus  composed  of  branch- 
ing, cylindrical,  thread-like  portions.  But  many  species, 
often  less  conspicuous,  are  crustaceous,  growing  as  if 
they  formed  part  of  the  bark  or  rock  to  which  they  are 
attached. 

332.  Fungi.  —  The  yeasts,  moulds,  rusts,  mildews,  and 
mushrooms  represent  an  immense  group  of  plants  of  which 
about  forty-five  thousand  species  are  now  known  in  the 
world.  They  range  from  the  very  simple  to  quite  com- 
plex forms,  growing  as  saprophytes  or  parasites  under  a 
great  variety  of  conditions.  Their  structure  and  life 
history  are  so  varied  as  to  constitute  a  long  series  of  divi- 
sions and  subdivisions.1  Chlorophyll  is  absent  from  fungi, 
and  they  are  destitute  of  starch,  but  produce  a  kind  of 
cellulose  which  appears  to  differ  chemically  from  that  of 
other  plants.  Unable  to  build  up  their  tissues  from  car- 
bonic acid  gas,  water,  and  other  mineral  matters,  they  are 
to  be  classed,  with  animals,  as  consumers  rather  than  as 
producers,  acting  on  the  whole  to  diminish  rather  than  to 
increase  the  total  amount  of  organic  material  on  the  earth. 


1  See  Strasburger,  Noll,  Schenk,  and  Schimper's  Text-Book  of  Botany, 
pp.  340-381  inch,  also  Potter  and  Warming's  Systematic  Botany,  p.  1,  and 
Engler's  Syllabus  der  Pflanzenfamilien,  Berlin,  1898,  pp.  25-47. 


TYPES  OF  CRYPTOGAMS;  THALLOPHYTES     275 

333.  Occurrence  and  Mode  of  Life  of  Fungi.  —  Among 
the  most  important  cryptogamous  plants  are  those  which, 
like  the  bacteria  of  consumption,  of  diphtheria,  of  typhoid 
fever,  or  of  cholera,  produce  disease  in  man  or  in  the 
lower  animals.  The  subclass  which  includes  these  plants 
is  known  by  the  name  Bacteria.  Bacteria  are  now  classed 
by  some  as  a  separate  group,  lower  than  fungi.  Some  of 
the  most  notable  characteristics  of  these  plants  are  their 
extreme  minuteness  and  their  extraordinary  power  of 
multiplication.  Many  bacteria  are  on  the  whole  highly 
useful  to  man,  as  is  the  case  with  those  which  produce 
decay  in  the  tissues  of  dead  plants  or  animals,  since  these 
substances  would,  if  it  were  not  for  the  destructive  action 
of  the  bacteria  of  putrefaction  and  fermentation,  remain 
indefinitely  after  death  to  cumber  the  earth  and  lock  up 
proteid  and  other  food  needed  by  new  organisms. 

The  mushrooms  and  their  allies  include  about  one-fourth 
of  the  fungi.  Some,  such  as  the  "  dry-rot "  fungus,  mis- 
takenly so  called,  cause  great  destruction  to  living  and 
dead  tree  trunks  and  timber  in  economic  use.  The  com- 
mon mushroom,  Agaricus  campestris,  is  the  most  important 
edible  species.  Probably  five  hundred  kinds  can  be  eaten, 
but  only  a  few  are  good  food,  and  even  these  contain  but  little 
nutriment.  Some  species  are  dangerous,  and  a  few  are  deadly 
poisons.  The  puffballs  are  a  small  group  allied  to  the  mush- 
rooms. Most  of  them  are  edible  and  of  good  quality. 

The  mildews  (Microsplicera,  etc.)  and  the  "black-knot" 
of  the  plum  trees  are  of  a  group  which  likewise  includes 
about  one-fourth  of  the  fungi.  A  considerable  number 
are  parasites,  injurious  to  vegetation,  while  thousands  of 
others  grow  on  dead  leaves,  twigs,  etc. 


276  FOUNDATIONS   OF  BOTANY 

The  "rust"  of  wheat  and  the  "smut"  of  corn  repre- 
sent groups  numbering  only  a  few  hundreds  of  species, 
which  are  very  important  because  they  are  all  parasites 
on  living  plants,  many  on  our  most  important  economic 
plants. 

Fig.  191,  representing  another  small  group  of  destruc- 
tive parasites,  shows  clearly  how  a  parasitic  fungus  grows 
from  a  spore  which  has  found  lodgment  in  the  tissues  of 
a  leaf  and  pushes  out  stalks  through  the  stomata  to  dis- 
tribute its  spores. 


CHAPTER   XXI 


mr 


TYPES   OF   CRYPTOGAMS;    BRYOPHYTES 

334,  The  Group  Bryophytes.  —  Under  this  head  are 
classed  the  liverworts  and  the  mosses.  Both  of  these 
classes  consist  of  plants  a  good  deal  more  highly  organized 
than  the  thallophytes. 
Bryophytes  have  no 
true  roots,  but  they 
have  organs  which 
perform  the  work  of 
roots.  Some  of  them 
have  leaves  (Fig.  206), 
while  others  haYe 
none  (Fig.  201). 
Fibro- vascular  bun- 
dles are  wanting.  The 
physiological  division 
of  labor  is  carried 
pretty  far  among  all 
the  bryophytes.  They 
have  special  appara- 
tus for  absorbing  FIG.  201.—  Part  of  Male  Thallus  of  a  Liverwort 
Water  and  Sometimes  (Marchantia  disjuncta).  (Enlarged.) 

„  -  .  ,  mr,  male  receptacle. 

for    conducting    it 

through  the  stem;  stomata  are  often  present  and  some- 
times highly  developed.  There  are  chlorophyll  bodies, 
often  arranged  in  cells  extremely  well  situated  for  acting 

277 


278 


FOUNDATIONS   OF  BOTANY 


on  the  carbon  dioxide  gas  which  the  plant  absorbs,  that  is, 
arranged  about  rather  large  air  chambers. 

Reproduction  is  of  two  kinds,  sexual  and  asexual,  and 
the  organs  by  which  it  is  carried  on  are  complicated  and 
highly  organized.  An  alternation  of  generations  occurs, 
that  is,  the  life  history  of  any  species  embraces  two  forms : 
a  sexual  generation,  which  produces  two  kinds  of  cells  that 

by  their  union  give 
rise  to  a  new  plant ; 
the  asexual  genera- 
tion, which  multiplies 
freely  by  means  of 
special  cells  known 
as  spores. 


FIG.  202.  — Part  of  Female  Thallus  of 
M.  disjuncta.    (Enlarged.) 

fr,  female  receptacle  ;  c,  cups  with  gemmae. 


THE   STUDY   OF 
MARCHANTIA 


335,    Occurrence.— 

Marchantia  grows  on  soil 
or  rocks  in  damp  shaded  places  and  is  widely  distributed. 

336,  The  Thallus.  — In  general  form  the  thallus  bears  some  resem- 
blance to  that  of  some  of  the  lichens,  as  Parmelia,  but  is  plainly 
different  in  color,  mode  of  branching,  arid  internal  structure  under 
the  microscope.  Under  the  microscope  (see  below)  the  individual 
cells  may  be  compared  with  those  of  the  medullary  layer  in  Physcia. 

Note  the  color  and  general  shape  of  the  thallus  and  study  care- 
fully the  mode  of  branching.  The  origin  of  the  growing  cells  is  at 
the  tip,  but  cells  so  originating  afterward  multiply  more  rapidly,  so 
that  the  tip  comes  to  be  in  a  notch. 

Viewing  the  thallus  as  an  opaque  object,  note  the  diamond-shaped 
network  on  the  upper  surface  and  the  dot-like  circle  in  the  middle 
of  each  diamond. 

Examine  the  under  surface  for  (1)  rhizoids  and  (2)  scales. 


TYPES   OF   CRYPTOGAMS ;  BRYOPHYTES 


279 


337.  Internal  Structure.  —  Cut  thin  cross-sections  of  the  thallus 
in  the  same  way  as  for  Physcia,  making  some  pass  through  the  cir- 
cular dots  mentioned  above.     Exam- 
ine under  a  high  power  and  note  the 
different   kinds   and   layers   of   cells 
composing   the    thallus.       Note   the 
character   of   the   cells   forming  the 
upper  and  lower  surfaces.     Describe 
the  cells  which  are  next  above  those 
of  the  lower  epidermis,  their  shape, 
color  of  contents,  approximate  num- 
ber of  horizontal  rows.     Have  they 
any  evident  intercellular  spaces  ?  Find 

FIG.  203.  — Section  through  Anther-  cells  connecting  these  with  the  upper 
idial  Receptacle  of  Marchantia.  epidermis  and  constituting  the  net- 
(Magnified.)  ,  .  ..  ,  , 

work  of  lines  seen  on  the  surface  of 
a,  antheridium. 

.the   thallus.      Note    the    air    cavity 

bounded  by  these  lines  and  the  loose  cells  which  occupy  it  in  part. 
What  is  the  color  of  their  contents  ?  How  are  they  attached,  and 
how  arranged?  Can  *you  discover  any 
opening  through  the  epidermis?  If  so, 
describe  it. 

Make  drawings  to  illustrate  the  details 
of  structure  observed. 

338.  Gemmae.  —  Look    for    a   thallus 
bearing   little  green  cups  formed  of  its 
own   substance.      Describe   the   contents 
of  the  cup.     The  bodies  are  called  gemmce. 
They  originate  by  vegetative  growth  alone 
and  when  detached  may  grow  into  new 
plants. 

339.  Fruiting  Organs.  —  Look  for  thalli 
bearing  stalks  with  umbrella-like  expan- 
sions.     The   Umbrellas  are  of  two  kinds,     «>  antheridium ;  az,  anthero- 

.     .        .,  zoids,  x  700. 

one   disk-like   with  crenate   points    (how 

many?)  and  the  other  has  rays  (how  many?)  elongated  and  curving 

downward.     Is  there  any  difference  in  the  height  of  the  two  kinds  ? 


az 


FIG.  204.  —  Sectional  View  of 
an  Antheridium  of  Mar- 
chantia. 


280 


FOUNDATIONS   OF  BOTANY 


Do  both  occur  on  the  same  thallus  ?     On  what  part  of  the  thallus 
do  they  occur,  and  do  they  differ  in  this  respect  ? 

340.  Antheridia.  —  The    antheridia   are   formed   as   outgrowths 
from  the  upper  surface  of  the  crenate  receptacle,  but  by  further 
growth  of  the  receptacle  they  become  imbedded.     They  should  be 
examined  under  a  high  power  and  sketched  in  outline.     The  anther- 
idium  produces  numerous  motile  antherozoids,  each  with  two  cilia. 

341.  Archegonia  and  Sporophytes.  —  The  receptacle  with  recurved 
rays  bears  the  archegonia.    Note  whether  they  occur  above  or  below 
and  in  what  relation  to  the  rays.    How  are  the  archegonia  protected  ? 

Note  the  cells  which  surround 
the  central  canal  and  form  the 
elongated  neck  of  the  archego- 
nium.  Does  the  archegonium 
open  upward  or  downward  ?  At 
the  base  look  for  the  germ-cell. 

The  antherozoids  enter  the 
central  canal  and  penetrating 
to  the  egg-cell  fertilize  it,  after 
which  it  begins  to  divide  and 
grows  into  a  sporophyte.  In  the 
older  specimens,  therefore,  the 
sporophytes  will  be  found  more 
or  less  developed.  The  archegonium  remains  upon  the  tip  of  the 
sporophytes.  The  mature  sporophyte  contains  the  spores  and  also 
peculiar  elongated  tapering  threads  with  spiral  thickenings.  These 
are  called  elaters. 

342.  Hepaticae.  —  Marchantia  represents   only  a  small 
division  of  the  Hepaticce,  and  is  not  typical  of  the  larger 
number  of  species.    In  spite  of  this  it  is  chosen  for  study, 
because  it  is  widely  distributed  and  more  available  for 
study  than  most  others.     In  most  species  the  fruit  lasts 
but  a  little  while  and  good  material  is  hard  to  obtain.     In 
Marchantia  the  fruiting  organs  are  abundant,  more  gradual 
in  their  development,  and  more  persistent.    Marchantia  and 


FIG.  205.  — Sectional  View  of  Female 
Receptacle  of  Marchantia.    (x  5.) 


TYPES  OF  CRYPTOGAMS;  BRYOPHYTES  281 

its  allies  consist  chiefly  of  the  thallus  in  the  vegetative  con- 
dition, while  the  greater  number  of  Hepaticse  have  a  stem 
and  leaves.  Thus  they  approach  closely  to  the  mosses. 
But  mosses  usually  have  leaves  on  all  sides  of  the  stem, 
while  the  leaves  of  Hepaticae  are  two-ranked,  spreading 
laterally,  with  sometimes  a  third  row  of  leaves  or  scales 
underneath.  The  leaves  of  mosses  usually  have  more  than 
one  layer  of  cells  in  some  part,  but  the  leaves  of  the  leafy 
Hepaticse  have  but  one  layer  of  cells  throughout.  The 
forms  of  the  leaves  are  often  very  curious  and  interesting. 
The  sporophyte  of  most  mosses  consists  of  a  capsule  with 
a  lid,  while  in  the  leafy  Hepaticse  the  capsule  usually 
opens  by  splitting  longitudinally  into  two  to  four  valves. 

Different  species  of  Hepaticee  grow  on  damp  soil,  rocks, 
and  the  bark  of  trees.  Many  are  capable  of  enduring 
drought  and  reviving  with  moisture. 

THE   STUDY   OF   PIGEON-WHEAT   MOSS 
(POLYTRICHUM   COMMUNE) 

343,  Occurrence.  —  This  moss  is  widely  distributed  over  the  sur- 
face of  the  earth,  and   some    of  its  relatives  are  among  the  best 
known    mosses    of    the  northern   United   States.      Here   it   grows 
commonly  in  dry  pastures  or   on  hillsides,  not  usually  in  densely 
shaded  situations. 

344.  Form,  Size,  and  General  Characters.  —  Study  several  speci- 
mens which  have  been  pulled  up  with  root-hairs.      Note  the  size, 
general  form,  color,  and  texture  of  all  the  parts  of  the  plants  exam- 
ined.    Some  of  them  probably  bear  spore-capsules  or  sporophytes  like 
those  shown  in  Fig.  206,  while  others  are  without  them.    Sketch  one 
plant  of  each  kind,  about  natural  size. 

What  difference  is  noticeable  between  the  appearance  of  the 
leaves  in  those  plants  which  have  spore-capsules  and  those  which 
have  none  ?  Why  is  this  ? 


282 


FOUNDATIONS   OF   BOTANY 


In  some  specimens  the  stem  may  be  found,  at  a  height  of  an  inch 
or  more  above  the  roots,  to  bear  a  conical,  basket-shaped  enlargement, 


FlG.  206.  —  A  Moss,  Catharinea. 

The  sporophytes  of  this  moss  are  usually  rather  more  slender  than 
here  represented. 


TYPES   OF   CRYPTOGAMS;   BRYOPHYTES  283 

out  of  the  center  of  which,  a  younger  portion  of  the  stem  seems  to 
proceed  ;  and  this  younger  portion  may  in  turn  end  in  a  similar 
enlargement,  from  which  a  still  younger  part  proceeds. 

Note  the  difference  in  general  appearance  between  the  leaves  of 
those  plants  which  have  just  been  removed  from  the  moist  collecting- 
box  and  those  which  have  been  lying  for  half  an  hour  on  the  table. 
Study  the  leaves  in  both  cases  with  the  magnifying  glass  in  order  to 
find  out  what  has  happened  to  them.  Of  what  use  to  the  plant  is 
this  change  ?  Put  some  of  the  partially  dried  leaves  in  water,  in  a 


prim 


FIG.  207.  —  Protonema  of  a  Moss. 

prim,  primary  shoot ;   h,  a  young  root-hair  ;  pi,  young  moss-plant ; 
br,  branches  of  primary  shoot. 

cell  on  a  microscope  slide,  cover,  place  under  the  lowest  power  of 
the  microscope,  and  examine  at  intervals  of  ten  or  fifteen  minutes. 
Finally  sketch  a  single  leaf. 

345.  Minute  Structure  of  the  Leaf  and  Stem.  —  The  cellular 
structure  of  the  pigeon-wheat  moss  is  not  nearly  as  simple  and  con- 
venient for  microscopical  study  as  is  that  of  the  smaller  mosses,  many 
of  which  have  leaves  composed,  over  a  large  part  of  their  surfaces, 
of  but  a  single  layer  of  cells,  as  shown  in  Fig.  209.  If  any  detailed 
study  of  the  structure  of  a  moss  is  to  be  made,  it  will,  therefore,  be 
better  for  the  student  to  provide  himself  with  specimens  of  almost 


284 


FOUNDATIONS   OF  BOTANY 


any  of  the  smaller  genera,1  and 
work  out  what  he  can  in  regard 
to  their  minute  anatomy. 


^.S^Wter 

•p\fr,~  * 

J 


b" 


FIG.  208.  — The  Antheridium 
of  a  Moss  (Funaria)  and  its 
Contents. 

a,  antheridium ;  6,  escaping 
antherozoids,  x  350  ;  c,  a  sin- 
gle antherozoid  of  another 
moss,  x  800. 


FIG.  209.  — Portions  of  Fertile  Plant 
of  a  Moss  (Funaria). 

A,  longitudinal  section  of  summit  of 
plant,  xlOO;  a,  archegonia ;  I, 
leaves  ;  J5,  an  archegonium,  x  550  ; 
e,  enlarged  ventral  portion  with 
central  cell ;  n,  neck  ;  m,  mouth. 


346.  Sporophytes.  —  That  part  of  the  reproductive  apparatus  of 
a  common  moss  which  is  most  apparent  at  a  glance  is  the  sporophyte 
or  spore-capsule  (Fig.  206).  This  is  covered,  until  it  reaches  maturity, 
with  a  hood  which  is  easily  detached.  Remove  the  hood  from  one 

1  As  Mnium  or  Bryum. 


TYPES   OF   CRYPTOGAMS;   BRYOPHYTES  285 

of  the  capsules,  examine  with  a  magnifying  glass,  and  sketch  it. 
Note  the  character  of  the  material  of  which  its  outer  layer  is 
composed. 

Sketch  the  uncovered  capsule  as  seen  through  the  magnifying 
glass,  noting  the  little  knob  at  its  base  and  the  circular  lid. 

Pry  off  this  lid,  remove  some  of  the  mass  of  spores  from  the 
interior  of  the  capsule,  observe  their  color  as  seen  in  bulk  through 
the  magnifying  glass,  then  mount  in  water,  examine  with  the  high- 
est obtainable  power  of  the  microscope,  and  sketch  them.  These 
spores,  if  sown  on  moist  earth,  will  each  develop  into  a  slender, 
branched  organism,  consisting,  like  pond-scum,  of  single  rows  of 
cells  (Fig.  207)  called  the  protonema. 

347.  Other  Reproductive  Apparatus.  —  The  student  cannot,  with- 
out spending  a  good  deal  of  time  and  making  himself  expert  in  the 
examination  of  mosses,  trace  out  for  himself  the  whole  story  of  the 
reproduction  of  any  moss.  It  is  sufficient  here  to  give  an  outline  of 
the  process.  The  protonema  develops  buds,  one  of  which  is  shown 
in  Fig.  207,  and  the  bud  grows  into  an  ordinary  moss  plant.  This 
plant,  in  the  case  of  the  pigeon-wheat  moss,  bears  organs  of  a  some- 
what flower-like  nature,  which  contain  either  antheridia  (Fig.  208), 
organs  which  produce  fertilizing  cells  called  antherozoids,  or  arche- 
gonia  (Fig.  209),  organs  which  produce  egg-cells,  but  in  this  moss 
antheridia  and  archegonia  are  not  produced  in  the  same  "moss- 
flower."  The  plants  therefore  correspond  to  dioecious  ones  among 
flowering  plants. 

After  the  fertilization  of  the  egg-cell,  by  the  penetration  of 
antherozoids  to  the  bottom  of  the  flask-shaped  archegonium,  the 
development  of  the  egg-cell  into  sporophyte  begins  ;  the  latter  rises 
as  a  slender  stalk,  while  the  upper  part  of  the  archegonium  is 
carried  with  it  and  persists  for  a  time  as  the  hood  or  calyptra. 


— /-^  i  L. 

,  OA«/P  ' b 

CHAPTER!  XXII 


TYPES    OF    CRYPTOGAMS;    PTERIDOPHYTES 

348.  The  Group  Pteridophytes.  —  Under  this  head  are 
classed  the  ferns,  the  scouring-rushes,  and  the  club-mosses. 
They  are  the  most  highly  organized  of  cryptogams,  having 
true  roots,  and  often  well-developed  stems  and  leaves. 

THE    STUDY   OF   A   FERN1 

349.  Conditions  of  Growth.  —  If  the  specimens  studied  were  col- 
lected by  the  class,  the  collectors  should  report  exactly  in  regard  to 
the  soil  and  exposure  in  wThich  the  plants  were  found  growing.     Do 
any  ferns   occur  in  surroundings  decidedly  different  from  these  ? 
What  kind  of  treatment  do  ferns  need  in  house  culture  ? 

350.  The  Underground  Portion.  —  Dig  up  the  entire  underground 
portion  of   a  plant  of  ladyfern.     Note  the  color,  size,  shape,  and 
appendages  of  the  rootstock.     If  any  are  at  hand  which  were  col- 
lected in  their  late  winter  or  early  spring  condition,  examine  into 
the  way  in  which  the  leafy  parts  of  the  coming  season  originate 
from  the  rootstock,  and  note  their  peculiar  shape  (Fig.  210,  A}. 
This  kind  of  vernation  (Sect.  136)  is  decidedly  characteristic  of  ferns. 
Observe  the  number  and  distribution  of  the  roots  along  the  rootstock. 
Bring  out  all  these  points  in  a  sketch. 

1  The  outline  here  given  applies  exactly  only  to  Asplenium  filix-foemina. 
Any  species  of  Asplenium  or  of  Aspidium  is  just  as  well  adapted  for  study. 
Cystopteris  is  excellent,  but  the  indusium  is  hard  to  find.  Polypodium  vul- 
gare  is  a  simple  and  generally  accessible  form,  but  has  no  indusium.  Pteris 
aquilina  is  of  world-wide  distribution,  but  differs  in  habit  from  most  of  our 
ferns.  The  teacher  who  wishes  to  go  into  detail  in  regard  to  the  gross  anat- 
omy or  the  histology  of  ferns  as  exemplified  in  Pteris  will  find  a  careful  study 
of  it  in  Huxley  and  Martin's  Biology,  or  a  fully  illustrated  account  in  Sedg- 
wick  and  Wilson's  Biology. 

286 


TYPES   OE   CRYPTOGAMS;   PTERIDOPHYTES          287 

351.  The  Frond.  — Fern  leaves  are  technically  known  as  fronds. 
Observe  how  these  arise  directly  from  the  rootstock. 

Make  a  somewhat  reduced  drawing  of  the  entire  frond,  which 
consists  of  a  slender  axis,  the  rhachis,  along  which  are  distributed 
many  leaflets  or  pinnce,  each  composed  of  many  pinnules.  Draw  the 
under  side  of  one  of  the  pinnae,  from  near  the  middle  of  the  frond, 
enlarged  to  two  or  three  times  its  natural  size,  as  seen  through  the 
magnifying  glass.  Note  just  how  each  pinnule  is  attached  to  its 
secondary  rhachis. 

Examine  the  under  side  of  one  of  the  pinnules  (viewed  as  an 
opaque  object  without  cover-glass)  with  the  lowest  power  of  the 
microscope,  and  note : 

(a)  The  "fruit-dots"  or  sori  (Fig.  210,  B)  (already  seen  with  the 
magnifying  glass,  but  now  much  more  clearly  shown). 

(5)  The  membranous  covering  or  indusium  of  each  sorus  (Fig. 
210,  C).  Observe  how  this  is  attached  to  the  veins  of  the  pinnule. 
In  such  ferns  as  the  common  brake  (Pteris)  and  the  maidenhair 
(Adiantum)  there  is  no  separate  indusium,  but  the  sporangia  are 
covered  by  the  incurved  edges  of  the  fronds. 

(c)  The  coiled  spore-cases  or  sporangia,  lying  partly  covered  by 
the  indusium.  How  do  these  sporangia  discharge  their  spores? 

Make  a  drawing,  or  several  drawings,  to  bring  out  all  these  points. 

Examine  some  of  the  sporangia,  dry,  with  a  power  of  about  fifty 
or  seventy-five  diameters,  and  sketch.  Scrape  off  a  few  sporangia, 
thus  disengaging  some  spores,  mount  the  latter  in  water,  examine 
with  a  power  of  about  200  diameters,  and  draw. 

352.  Life  History  of  the  Fern.  —  When  a  fern-spore  is  sown  on 
damp  earth  it  gradually  develops  into   a  minute,  flattish   object, 
called  a  prothallium  (Fig.  211).     It  is  a  rather  tedious  process  to 
grow  prothallia  from  spores,  and  the  easiest  way  to  get  them  for 
study  is  to  look  for  them  on  the  earth  or  on  the  damp  outer  surface 
of  the  flower-pots  in  which  ferns  are  growing  in  a  greenhouse.     All 
stages  of  germination  may  readily  be  found  in  such  localities. 

Any  prothallia  thus  obtained  for  study  may  be  freed  from  par- 
ticles of  earth  by  being  washed,  while  held  in  very  small  forceps,  in 
a  gentle  stream  of  water  from  a  wash-bottle.  The  student  should 
then  mount  the  prothallium,  bottom  up,  in  water  in  a  shallow  cell, 


288 


FOUNDATIONS  OF  BOTANY 


FIG.  210.  — Spore-Plant  of  a  Fern  (Aspidium  Filix-mas). 

A,  part  of  rootstock  and  fronds,  not  quite  one-sixth  natural  size  ;  fr,  young  fronds 
unrolling ;  £,  under  side  of  a  pinnule,  showing  sori,  s  ;  C,  section  through  a 
sorus  at  right  angles  to  surface  of  leaf,  showing  indusium,  i,  and  sporangia,  s  ; 
D,  a  sporangium  discharging  spores.  (B  is  not  far  from  natural  size.  C  and 
D  are  considerably  magnified.) 


TYPES   OF   CRYPTOGAMS;   PTERIDOPHYTES          289 


cover  with  a  large  cover-glass,  and  examine  with  the  lowest  power 
of  the  microscope.     Note  : 

(a)  The  abundant  root-hairs,  springing  from  the  lower  surface 
of  the  prothallium. 

(&)  The  variable   thickness  of  the  prothallium,  near  the  edge, 
consisting  of  only  one  layer  of  cells. 

(c)  (In  some  mature  specimens)  the  young  fern  growing  from 
the  prothallium,  as  shown  in  Fig.  211,  B. 

The  student  can  hardly  make  out  for  himself,  without  much 
expenditure  of  time,  the  structure  of  the  antheridia  and  the  arche- 
gonia  (Fig.  211,  4), 
by  the  cooperation 
of  which  fertilization 
takes  place  on  much 
the  same  plan  as  that 
already  described  in 
the  case  of  mosses. 
The  fertilized  egg- 
cell  of  the  archego- 
nium  gives  rise  to 
the  young  fern,  the 
sporopJiyte  which 
grows  at  first  at  the 
expense  of  the  parent 
prothallium  but  soon 
develops  roots  of  its 
own  and  leads  an  in- 
dependent existence. 

353.  Nutrition.— 
The  mature  fern 
makes  its  living,  as  flowering  plants  do,  by  absorption  of  nutritive 
matter  from  the  soil  and  from  the  air,  and  its  abundant  chlorophyll 
makes  it  easy  for  the  plant  to  decompose  the  supplies  of  carbon 
dioxide  which  it  takes  in  through  its  stoinata. 


FIG.  211.  — Two  Prothallia  of  a  Fern  (Aspidium). 
A,  under  surface  of  a  young  prothallium  ;  ar,  arche- 
gonia ;  an,  antheridia  ;  r,  rhizoids  ;  B,  an  older  pro- 
thallium  with  a  young  fern-plant  growing  from  it ; 
I,  leaf  of  young  fern.    (Both  x  about  8.) 


290  FOUNDATIONS  OF  BOTANY 


FERNS 

354.  Structure,  Form,  and  Habits  of  Ferns. —  The  struc- 
ture of  ferns  is  much  more  complex  than  that  of  any  of 
the  groups  of  cryptogamous  plants  discussed  in  the  earlier 
portions  of  the  present  chapter.     They  are  possessed  of 
well-defined  nbro-vascular  bundles,  they  form  a  variety  of 
parenchymatous  cells,  the  leaves  have  a  distinct  epidermis 
and  are  provided  with  stomata 

Great  differences  in  size,  form,  and  habit  of  growth  are 
found  among  the  various  genera  of  ferns.  The  tree  ferns 
of  South  America  and  of  many  of  the  islands  of  the  Pacific 
Ocean  sometimes  rise  to  a  height  of  forty  feet,  while  the 
most  minute  species  of  temperate  and  colder  climates  are  not 
as  large  as  the  largest  mosses.  Some  species  climb  freely, 
but  most  kinds  are  non-climbing  plants  of  moderate  size, 
with  well-developed  rootstocks,  which  are  often,  as  in  the 
case  of  the  bracken-fern,  or  brake,1  and  in  Osmunda,  very 
large  in  proportion  to  the  parts  of  the  plant  visible  above 
ground. 

355.  Economic  Value  of  Ferns.  —  Ferns  of  living  species 
have  little  economic  value,  but  are  of  great  interest,  even 
to  non-botanical  people,  from  the  beauty  of  their  foliage. 

During  that  vast  portion  of  early  time  known  to  geolo- 
gists as  the  Carboniferous  Age,  the  earth's  surface  in  many 
parts  must  have  been  clothed  with  a  growth  of  ferns  more 
dense  than  is  now  anywhere  found.  These  ferns,  with 
other  flowerless  herbs  and  tree-like  plants,  produced  the 
vegetable  matter  out  of  which  all  the  principal  coal  beds 
of  the  earth  have  been  formed. 

1  Pteris  aquilina. 


TYPES    OF   CRYPTOGAMS;   PTERIDOPHYTES 

356.  Reproduction  in  Ferns. — The  reproduction  of  ferns 
is  a  more   interesting   illustration   of  alternation  of  gen- 
erations than  is  afforded  by  mosses.      The  sexual  plant, 
gametophyte,    is   the    minute    pro  thallium,   and   the    non- 
sexual  plant,  sporophyte,   which  we    commonly  call   the 
fern,  is  merely  an  outgrowth  from  the  fertilized  egg-cell, 
and  physiologically  no  more  important  than  the  sporophyte 
of  a  moss,  except  that  it  supplies  its  own  food  instead  of 
living  parasitically.     Like  this  sporophyte,  the  fern  is  an 
organism  for  the  production  of   vegetative  spores,  from 
which  new  plants  endowed  with  reproductive  apparatus 
may  grow. 

THE    STUDY   OF   A    CLUB-MOSS    (LYCOPODIUM) 

357.  Occurrence.  —  Several  species  of  Lycopodium  are  common  in 
rich  woods  in  the  northern  and  mountainous  portions  of  the  eastern 
United  States.     Any  species  may  be  studied. 

358.  Examination. — Note  whether  the  plant  is  chiefly  erect  or 
prostrate  and  vine-like.     Describe  the  mode  of  branching.     Are  the 
leaves  arranged  flat-wise  or  equally  on  all  sides  of  the  stem  ?   Describe 
the  leaves  briefly.     Are  they  all  of  one  kind  or  do  some  portions  of 
the  plant  evidently  have  smaller  leaves  ? 

Select  fruiting  specimens  and  determine  the  position  of  the  spo- 
rangia. Is  the  leaf,  near  whose  base  each  sporangium  is  situated,  like 
the  ordinary  foliage  leaves  of  the  plant  ?  Are  the  fruiting  portions 
of  the  plant  similar  in  general  aspect  or  different  from  the  rest  of 
the  plant  and  raised  above  it  on  stalks  ?  Examine  the  spores.  Are 
they  all  of  one  kind  ? 

If  Selaginella  is  used  in  place  of  Lycopodium  or  for  comparison, 
two  kinds  of  sporangia  are  to  be  sought,  differing  chiefly  in  shape. 
Describe  each  briefly.  Compare  the  number  of  spores  in  each.  The 
larger  spores  (macrospores)  germinate  and  at  length  produce  pro- 
thallia  bearing  archegonia,  while  the  smaller  produce  prothallia 
bearing  antheridia.  The  archegonia,  after  fertilization,  develop  each 


292 


FOUNDATIONS   OF  BOTANY 


an  embryo.     This  grows,  remaining   for   a  time  attached  to  the 
macrospore,  and  at  length  forms  a  new  spore-plant. 

THE   STUDY   OF   A   SCOURING-RUSH  (EQUISETUM} 

359.  Occurrence.  —  The  common  horse-tail,  Equisetum  arvense,  is 
widely  distributed  in  the  United  States,  east,  west,  north,  and  south. 
It  is  very  often  found  on  sand  hills  and  along  railroad  embankments. 


FIG.  212.  —  Plant  of  Lycopodium  (L.  annotinum). 

The  fruiting  stems  appear  very  early  in  the  spring  and  are  of  short 
duration.  The  sterile  vegetative  growth  follows,  becoming  well 
grown  in  June. 

360.  Examination  of  Rootstocks  and  Roots.  —  Examine  the  under- 
ground portions  of  the  plant  with  reference  to  general  size,  position, 
color,  shape,  and  position  of  notches.  After  studying  the  stems 


TYPES   OF   CRYPTOGAMS;   PTERIDOPHYTES          293 


above  ground  insert  here  any  evident  points  of  comparison.  Do  you 
find  any  special  forms  of  stern  development  suited  to  a  special  pur- 
pose ?  Are  there  any  organs  in  the  nature  of  leaves  ? 


FIG.  213.  — A  Scouring-Rush  (Equisetum  sylvatlcum).  At  the  right  is  a 
colorless  fertile  stem,  in  the  middle  a  green  sterile  one,  and  at  the 
left  a  green  fertile  one. 


294  FOUNDATIONS   OF   BOTANY 

361.  Sterile  Stems. — Examine    the    stems  above   ground  with 
reference  to  their  color  and  mode  and  degree  of  branching.     What 
is  the  character  of  the  leaves  ?     Do  the  stems  in  any  sense  serve  as 
leaves?     Observe  the  nodes  composing  the  stem  and  note  the  posi- 
tion of  the  leaves  on  the  stems.     Do  they  appear  to  be  placed  several 
at  the  same  level  (whorled)  ? 

Examine  with  a  magnifying  glass  the  surface  of  the  stem  and 
note  the  number  of  ridges  and  grooves.  Compare  the  number  and 
position  of  the  leaves  with  reference  to  these. 

362.  Mineral  Matter  in  Stem.  —  Treat  small  pieces  of  the  stem 
with  strong  nitric  acid  to  remove  all  vegetable  substance  and  note 
the  mineral  substance  remaining.     Treat  in  a  similar  way  thin  cross- 
sections  and   examine  under   the   microscope.      The   substance    is 
silica.     It  gives  the  plant  its  gritty  feeling  and  its  name  and  use  as 
"  scouring-rush."     Of  what  use  is  it  to  the  plant?     Use  of  the  same 
substance  in  outer  rind  of  corn  stem,  bamboo  stem,  and  straw  of 
grains  ? 

363.  Microscopic  Examination.  —  Make  thin  cross-sections  of  the 
stem  and  examine  under  the  lowest  power  of  the  microscope.     Make 
a  diagrammatic  sketch  to  indicate  the  central  cavity,  the  number 
and  position  of  the  fibro-vascular  bundles,  the  cavity  or  canal  in 
each,  the  ring  of  tissue  surrounding  the  ring  of  bundles,  and  the 
larger  cavities  or  canals  outside  of  this.     Where  is  the  chlorophyll 
located?     Can  stomata  be  found,  and  if  so,  what  is  their  location 
and  arrangement? 

364.  Fertile  Stems.  — Describe  the  fruiting  stem  with  reference  to 
general  aspect,  size,  color,  number,  and  length  of  internodes,  position 
of  spore-bearing  portion,  color  of  spores  in  mass.     Note  the  shield- 
shaped  bodies   (transformed  leaves  or  iporophylls}   composing  the 
cone-like  "flower"  and  see  whether  any  joints  can  be  detected  where 
they  are  attached.     Examine  the  inner   surface  of  the  shields  for 
sporangia  and  spores.     Examine  the  sporangia  under  a  low  power 
of  the  microscope.      Examine  some  spores  under  a  higher  power. 
Note  the  two  bands,  elaters,  on  each  spore,  crossing  each  other  and 
attached  only  at  the  point  of  crossing,  forming  four  loose  appendages. 
Watch  these  while  some  one  moistens  them  by  gently  breathing 
upon  them  as  they  lie  uncovered  on  the  slide  under  the  microscope 


TYPES   OF   CRYPTOGAMS;   PTERIDOPHYTES          295 

and  note  the  effect.     Also  note  the  effect  of  drying.     How  does  this 
affect  the  spores  ?     Use  of  the  bands  ? 

365.  Germination  of  Spores.  —  The  spores  germinate  while  fresh 
and  form  prothallia  corresponding  to  those  of  ferns,  but  generally 
dioecious.     The   prothallium  which    bears  the  antheridia   remains 
comparatively  small,  and  the  antheridia  are  somewhat  sunken.     The 
others  grow  much  larger  and  branch  profusely. 

The  terminal  portion  becomes  erect  and  ruffled. 
Near  this  part  the  archegonia  are  formed,  quite 
similar  to  those  of  ferns.  The  embryo  plant 
developing  from  the  germ-cell  has  its  first  leaves 
in  a  whorl.  This  at  length  grows  into  a  spore- 
plant  like  that  shown  in  Fig.  213. 

About  twenty-five  species  of  Equisetum  are 
known.  Several  may  be  looked  for  in  any 
locality  and  may  well  be  compared  with  the  one 
described  above,  in  regard  to  form,  mode  of 
branching,  and  mode  of  fruiting.  .  . 

366.  Fern-Plants     (Pteridophytes).  - 
The  Pteridophytes  (literally  fern-plants) 
include  in  their  general  category  not  only 
ferns  as  commonly  recognized,  but  several 
other  small  groups  which  are  very  inter- 
esting on  account  of  their  diversity.    All 
cryptogams  higher  than  mosses  belong  in 
this  group.     In  moss  plants  the  individ- 
uals growing  from   spores    and   bearing 
antheridia  and  archegonia,  the  gameto- 
phytes,  are  full-grown  leafy  plants,  and 

the  spore-bearing  plant,  or  sporophyte,  is   FlG.214._Part  of  a 
merely  a  stalk  bearing  a  sporangium.     In      Lobe  of  the  Mature 

T,     ,,         ,,  Female   Prothal- 

all  the   tern-plants   the  reverse  is  true.      iium  Of  Equisetum. 
The  individuals  growing  from  spores  and      (x  about  ^ 

i  .,        .  ,.  .     a,  mouth  of  a  ferti- 

beanng  antheridia  and  archegonia  are  of 


296  FOUNDATIONS   OF  BOTANY 

minor  vegetative  development  (prothallia),  while  the  spore- 
bearing  plant  is  a  leafy  plant,  even  a  tree  in  some  ferns. 

The  ferns  in  the  strictest  sense  have  sporangia  derived 
from  the  epidermis  (transformed  hairs),  while  a  few  plants 
closely  resembling  them  in  general  aspect  (BotrycTiium,  etc.) 
have  .sporangia  formed  in  the  tissue  of  the  leaf. 

In  the  next  subdivision,  the  water-ferns  (Fig.  215),  there 
is  little  resemblance  to  the  common  ferns.  The  sporangia 
are  in  special  receptacles  at  the  basal  portion  of  the  plant. 
The  spores  are  of  two  kinds,  dioecious,  one  on  germination, 
producing  antheridia,  the  other  archegonia.  This  group 
includes  two  rooting  forms,  Marsilea  (with  leaves  resem- 
bling a  four-leaved  clover)  and  Pilularia,  bearing  simple 
linear  leaves,  and  two  floating  forms,  Salvinia  (Fig.  215) 
and  Azolla. 

The  remaining  groups  of  fern-plants  are  the  horse-tails 
and  the  club-mosses.  The  horse-tails  have  only  one  kind 
of  spore  and  are  peculiar  chiefly  in  their  vegetative  aspect 
(Fig.  213),  while  the  spore-bearing  leaves,  or  sporophylls, 
are  arranged  in  the  form  of  a  cone,  as  already  shown. 

The  club-mosses  include  some  plants  which,  as  their 
name  implies,  have  a  superficial  resemblance  to  a  large 
moss,  with  the  addition  of  a  club-shaped  stalked  fruiting 
spike.  These  are  the  so-called  "  ground  pines  "  and  the 
running  ground  "  evergreens  "  used  for  Christmas  festoons 
in  New  England.  Technically  the  group  is  distinguished 
by  the  possession  of  firm-walled  sporangia  formed  singly 
near  the  bases  of  the  leaves.  The  ordinary  club-mosses 
already  referred  to  have  but  one  kind  of  spore,  while 
plants  called  Selaginella  and  Isoetes  have  two  kinds  of 
spores,  in  this  respect  resembling  Marsilea.  In  many 


TYPES  OF  CRYPTOGAMS;  PTERtDOPHYTES          297 

species  of  Selaginella  the  leaves  are  arranged  flat-wise  on 
the  stem,  so  that  considered  physiologically  the  branch- 
ing stem  and  its  leaves  together  serve  as  a  foliage  leaf. 
In  one  of  the  commonest  American  forms,  however,  the 
stem  is  more  nearly  erect,  and  the  leaves  are  all  alike  and 
four-ranked. 

Isoetes  (quill-wort)  grows  attached  to  the  soil  in  shallow 
water  at  the  bottoms  of  ponds.  It  has  the  aspect  of  short 
grass  growing  in  bunches.  The  large  sporangia  are  at  the 
broad  bases  of  the  leaves. 

367.  High  Organization  of  Pteridophytes.  —  The  student 
may  have  noticed  that  in  the  scouring-rush  and  the  club- 
moss  studied  there  are  groups  of  leaves  greatly  modified 
for  the  purpose  of  bearing  the  sporangia.  These  groups 
are  more  nearly  equivalent  to  flowers  than  anything  found 
in  the  lower  spore-plants,  and  the  fern-plants  which  show 
such  structures  deserve  to  be  ranked  just  below  seed-plants 
in  any  natural  system  of  classification. 

The  variety  of  tissues  which  occur  in  pteridophytes  is 
frequently  nearly  as  great  as  is  found  in  ordinary  seed- 
plants,  and  the  fibro- vascular  system  is  even  better  devel- 
oped in  many  ferns  than  in  some  seed-plants. 

Starch-making  is  carried  on  by  aid  of  abundant  chloro- 
phyll bodies  contained  in  parenchyma-cells  to  which  car- 
bonic acid  gas  is  admitted  by  stomata.  In  many  cases 
large  amounts  of  reserve  food  are  stored  in  extensive  root- 
stocks,  so  that  the  spring  growth  of  leaves  and  stems  is 
extremely  rapid. 


CHAPTER    XXIII 
THE    EVOLUTIONARY    HISTORY   OF   PLANTS 

368.  The  Earliest  Plant  Life.  —What  sort  of  plants  first 
appeared  on  the  earth  has  never  been  positively  ascertained. 
The  oldest  known  rocks  contain  carbon  (in  the  form  of 
black  lead  or  graphite)  which  may  represent  the  remnants 
of  plants  charred  at  so  high  a  temperature  and  under  so 
great  pressure  as  to  destroy  all  traces  of  plant  structure. 
Some  objects  supposed  by  many  to  be  the  remains  of  large 
algae  have  been  found  in  rocks  that  date  back  to  a  very 
early  period  in  the  life  history  of  the  earth,  before  there 
were  any  backboned  animals,  unless  possibly  some  fishes. 
Judging  from  the  way  in  which  the  various  groups  of 
plants  have  made  their  appearance  from  the  time  when 
we  can  begin  clearly  to  trace  their  introduction  upon  the 
earth,  it  is  probable  that  some  of  the  simplest  and  lowest 
forms  of  thallophytes  were  the  first  to  appear.     Decaying 
animal  or  vegetable  matter  must  have  been  less  abundant 
than  is  now  the  case,  so  that  a  plant  that  could  make 
part  or  all  of  its  food  from  raw  materials  would  have  had 
a  better  chance  than  a  saprophyte  that  could  not.    Water- 
plants  are  usually  simpler  than  land-plants,  so  it  is  highly 
probable  that  some  kind  of  one-celled  aquatic  alga  was 
the  first  plant. 

369.  Fossil  Plants. — Fossils  are  the  remains  or  traces 
of  animals  or  plants    preserved  in  the  earth  by  natural 
processes.     Fossil  plants,    or   parts    of   plants,    are    very 

298 


THE   EVOLUTIONARY    HISTORY    OF   PLANTS          299 

common  ;  the  impressions  of  fern-leaves  in  bituminous  coal 
and  pieces  of  wood  turned  into  a  flint-like  substance  are 
two  of  the  best  known  examples. 

The  only  way  in  which  we  can  get  knowledge  about 
the  animals  and  plants  that  inhabited  the  earth's  surface 
before  men  did  is  by  studying  such  rocks  as  contain  the 
remains  of  living  things.  In  this  way  a  great  deal  of 
information  has  been  gained  about  early  forms  of  animal 
life  and  a  less  amount  about  early  plant  life,  —  less  because 
as  a  general  thing  plants  have  no  parts  that  would  be 
as  likely  to  be  preserved  in  the  rocks  as  are  the  bones 
and  teeth  of  the  higher  animals  and  the  shells  of  many 
lower  ones. 

370.  The  Law  of  Biogenesis.  —  An  extremely  important 
principle  established  by  the  study  of  the  development  of 
animals  and  plants  from  the  egg  or  the  seed,  respectively, 
to  maturity  is  this  :  The  development  of  every  individual  is 
a  brief  repetition  of  the  development  of  its  tribe.  The  prin- 
ciple just  stated  is  known  as  the  law  of  biogenesis.  As 
eggs  develop  during  the  process  of  incubation,  the  young 
animals  within  for  a  considerable  time  remain  much  alike, 
and  it  is  only  at  a  comparatively  late  stage  that  the  wing 
of  the  bird  shows  any  decided  difference  from  the  fore-leg 
of  the  alligator  or  the  turtle.  Zoologists  in  general  are 
agreed  that  this  likeness  in  the  early  stages  of  the  life 
history  of  such  different  animals  proves  beyond  reasonable 
doubt  that  they  all  have  a  common  origin,  that  is,  are 
descended  from  the  same  kind  of  ancestral  animal. 

Among  plants  the  liverworts  and  ferns  supply  an  excel- 
lent illustration  of  the  same  principle.  In  both  of  the  groups 
the  fertilized  egg-cells,  as  the  student  may  have  learned 


300  FOUNDATIONS   OF  BOTANY 

by  his  own  observations,  are  much  alike.  As  the  egg-cell 
grows  and  develops,  the  sporophyte  of  a  liverwort,  which 
proceeds  from  the  egg-cell,  is  extraordinarily  unlike  the 
"fern"  or  asexual  generation  (sporophyte)  among  Filices. 
Now  this  progressive  unlike  ness  between  liverworts  and 
ferns,  as  they  develop  from  the  fertilized  egg-cell,  points  to 
the  conclusion  that  both  groups  of  plants  have  a  common 
origin  or  that  the  more  highly  organized  ferns  are  direct 
descendants  of  the  less  highly  organized  liverworts. 

371.  Plants  form  an  Ascending  Series.  —  All  modern 
systems  of  classification  group  plants  in  such  a  way  as  to 
show  a  succession  of  steps,  often  irregular  and  broken, 
seldom  leading  straight  upward,  from  very  simple  forms 
to  highly  complex  ones.  The  humblest  thallophytes  are 
merely  single  cells,  usually  of  microscopic  size.  Class 
after  class  shows  an  increase  in  complexity  of  structure 
and  of  function  until  the  most  perfectly  organized  plants 
are  met  with  among  the  dicotyledonous  angiosperms. 
During  the  latter  half  of  the  present  century  it  first 
became  evident  to  botanists  that  among  plants  deep-seated 
resemblances  imply  actual  relationship,  the  plants  which 
resemble  each  other  most  are  most  closely  akin  by  descent, 
and  (if  it  were  not  for  the  fact  that  countless  forms  of  plant 
life  have  wholly  disappeared)  the  whole  vegetable  kingdom 
might  have  the  relationships  of  its  members  worked  out  by  a 
sufficiently  careful  study  of  the  life  histories  of  individual 
plants  and  the  likeness  and  differences  of  the  several  groups 
which  make  up  the  system  of  classification.1 

1  See  Campbell's  Evolution  of  Plants  and  Warming's  Systematic  Botany, 
Preface  and  throughout  the  work.  In  the  little  flora  of  the  present  book,  the 
families  are  arranged  in  the  order  which,  according  to  the  best  recent  German 
authorities,  most  nearly  represents  their  relationships. 


THE   EVOLUTIONARY   HISTORY   OF  PLANTS          301 

372.  Development  of  the  Plant  from  the  Spore  in  Green 
Algae,   Liverworts,  and  Mosses. — The    course  which   the 
forms  of  plant  life  have  followed  in  their  successive  ap- 
pearance on  the  earth  may  be  traced  by  the  application 
of  the  law  above  named.     Such  algge  as  the  pond-scums 
produce  spores  which  give  rise  directly  to  plants  like  the 
parent. 

In  many  liverworts  the  spore  by  its  germination  produces 
a  thallus  which  at  length  bears  antheridia  and  archegonia. 
The  fertilized  archegonium  develops  into  a  sporophyte 
which  remains  attached  to  the  thallus,  although  it  is  really 
a  new  organism.  Liverworts,  then,  show  an  alternation  of 
generations,  one  a  sexual  thallus,  the  gametophyte,  the 
next  a  much  smaller,  non-sexual  sporophyte,  and  so  on. 

A  moss-spore  in  germination  produces  a  thread-like  pro- 
tonema  which  appears  very  similar  to  green  algee  of  the 
pond-scum  sort.  This  at  length  develops  into  a  plant  with 
stem  and  leaves,  the  sexual  generation  of  the  moss*  The 
fertilized  archegonium  matures  into  a  sporophyte  which  is 
the  alternate,  non-sexual  generation.  This  is  attached  to 
the  moss-plant,  or  gametophyte,  but  is  an  important  new 
organism.  In  the  moss,  as  in  the  liverwort,  the  sexual 
generation  is  the  larger  and  the  more  complex  ;  the  non- 
sexual  generation  being  smaller  and  wholly  dependent  for 
its  food  supply  on  the  other  generation,  to  which  it  is 
attached. 

373,  Development  of  the  Plant  from  the  Spore  in  Pterido- 
phytes.  —  In  the  pteridophytes  there  is  an  alternation  of 
generations,  but  here  the  proportions  are   reversed,  the 
prothallium,  or  sexual  generation,  or  gametophyte,  being 
short-lived   and   small    (sometimes  microscopic),  and  the 


302 


FOUNDATIONS   OF  BOTANY 


non-sexual  generation,  the  sporophyte,  often  being  of  large 

size.  The  ferns  (non-sexual  generation),  for  instance,  are 
perennial  plants,  some  of  them  tree- 
like. 

Some  pteridophytes,  as  the  Salvinia, 
a  small  floating  aquatic  plant,  some- 
times known  as  a  water-fern  (Fig. 
215),  produce  two  kinds  of  spores, 
the  large  ones  known  as  macrospores, 
and  the  small  ones  known  as  micro- 
spores  (Fig.  216).  Both  kinds  pro- 
duce microscopic  prothallia,  those  of 
the  former  bearing  only  archegonia, 
those  of  the  latter  only  antheridia. 
From  the  prothallia  of  the  macro- 
spores  a  plant  (non-sexual  generation) 
of  considerable  complexity  of  struc- 
ture is  formed. 
374.  Parts  of  the  Flower  which  correspond  to  Spores.  — 

In  seed-plants  the  spore-formation  of  cryptogams  is  repre- 
sented,   though    in    a    way    not 

at    all    evident   without   careful 

explanation.       The   pistil  is  the 

macrospore-producing  leaf  or  mac- 

rosporophyll,   and  the  stamen  is 

the  microspore-producing  leaf  or 

microsporopTiyll.     Pines  and  other 

gymnospenns  produce  a  large  cell 

(the    embryo    sac)    in   the    ovule 

(Fig.   217),  which  corresponds  to  the  macrospore,  and  a 

pollen  grain    which    represents  the    microspore.      In  its 


FIG.  215.— A  Water-Fern 
(Salvinia). 


ma 


FIG.  216.— Twolndusiaof  Salvinia. 

mi,  microspores  ;  ma,  macro- 
spores. 


THE   EVOLUTIONARY   HISTOKY   OF  PLANTS 


303 


development  the  macrospore  produces  an  endosperm  which 
is  really  a  small  cellular  prothallium,  concealed  in  the  ovule. 
The  microspore  contains  vestiges  of  a  minute  prothallium. 

In  the  angiosperms  the  macrospore  and  its  prothallium 
are  still  less  developed,  and  the 
microspore,  or  pollen  grain,  has 
lost  all  traces  of  a  prothallium 
and  is  merely  an  antheridium 
which  contains  two  generative 
cells.1  These  are  most  easily 
seen  in  the  pollen  grain,  but 
sometimes  they  are  plainly  visi- 
ble in  the  pollen  tube  (Fig.  164). 
Phanerogams  are  distinguished 
from  all  other  plants  by  their 
power  of  producing  seeds,  or 
enclosed  macrosporangia,  with 
embryos. 

375.  The  Law  of  Biogenesis 
and  the  Relationships  of  the  Great 
Groups  of  Plants.  —  On  summing 
up  Sects.  372-374  it  is  evident 
that  the  sexual  generation  in 
general  occupies  a  less  and  less 
important  share  in  the  life  of  the 
plant  as  one  goes  higher  in  the  scale  of  plant  life.2  In  the 
case  of  the  rockweed,  for  instance,  the  sexual  generation 
is  the  plant.  Among  mosses  and  liverworts  the  sexual 

1  Sometimes  only  one  generative  cell  escapes  from  the  pollen  grain  into  the 
pollen  tube,  and  there  it  divides  into  two  cells. 

2  A  good  many  plants  of  low  organization,  however,  are  not  known  to  pass 
through  any  sexual  stage. 


FIG.  217.  — Longitudinal  Section 
through  Fertilized  Ovule  of  a 
Spruce. 

p,  pollen  grains  ;  t,  pollen  tubes  ; 
n,  neck  of  the  archegonium  ; 
a,  body  of  archegonium  with 
nucleus  ;  e,  embryo  sac  tilled 
with  endosperm. 


304  FOUNDATIONS   OF  BOTANY 

generation  is  still  very  prominent  in  the  life  of  the  plant. 
Ordinary  ferns  show  us  the  sexual  generation  existing  only 
as  a  tiny  independent  organism,  living  on  food  materials 
which  it  derives  from  the  earth  and  air.  In  the  Salvinia 
it  is  reduced  to  microscopic  size  and  is  wholly  dependent 
on  the  parent-plant  for  support.  Among  seed-plants  the 
sexual  generation  is  so  short-lived,  so  microscopic,  and  so 
largely  enclosed  by  the  tissues  of  the  flower  that  it  is  com- 
paratively hard  to  demonstrate  that  it  exists. 

The  fact  that  the  life  history  of  so  many  of  the  classes 
of  plants  embraces  a  sexual  stage,  in  which  an  egg-cell  is 
fertilized  by  some  sort  of  specialized  cell  produced  wholly 
for  use  in  fertilization,  tends  strongly  to  show  the  com- 
mon origin  of  the  plants  of  all  such  classes.  We  have 
reason  to  believe,  from  the  evidence  afforded  by  fossils, 
that  plants  which  have  only  a  sexual  generation  are 
among  the  oldest  on  the  earth.  It  is  therefore  likely  that 
those  which  spend  the  least  portion  of  their  entire  life  in 
the  sexual  condition  were  among  the  latest  of  plants  to 
appear.  Then,  too,  those  which  have  the  least  developed 
sexual  generation  are  among  the  latest  of  plants.  Judged 
by  these  tests  the  angiosperms  must  be  the  most  recently 
developed  of  all  plants. 

If  one  were  to  attempt  to  arrange  all  the  classes  of 
existing  plants  in  a  sort  of  branching  series  to  show  the 
way  in  which  the  higher  plants  have  actually  descended 
from  the  lower,  he  would  probably  put  some  one  of  the 
green  algse  at  the  bottom  and  the  angiosperms  at  the  top 
of  the  series. 

376,  The  Oldest  Angiosperms.  —  It  is  impossible  to  give 
any  of  the  reasons  for  the  statements  of  this  section 


THE   EVOLUTIONARY   HISTORY   OF  PLANTS          305 

without  making  an  unduly  long  chapter.  Briefly,  it  may 
be  stated  that  the  monocotyledons  are  the  simplest  and 
probably  the  oldest  angiosperms;  the  dicotyledons  are 
higher  in  organization  and  came  later.  The  descent  and 
various  relationships  of  the  families  of  dicotyledons  can 
be  discovered  by  the  study  of  the  flower,  fruit,  and  seed 
better  than  by  the  examination  of  the  vegetative  organs. 

The  entire  pedigree  of  the  several  families  cannot  be 
represented  by  arranging  the  names  of  the  families  in  a 
straight  line.  It  is,  however,  in  a  general  way,  as  indi- 
cated by  the  succession  of  families  in  the  Flora  which 
accompanies  this  book,  the  Willow  Family  being  perhaps 
the  oldest  (of  the  more  familiar  ones)  and  the  Composite 
Family  the  youngest. 


PART  II 

ECOLOGY 

CHAPTER    XXIV 
PLANT   SOCIETIES 

377,  Ecology.  —  Plant  ecology  includes  all  that  portion 
of  botany  which  has  to  do  with  the  way  in  which  plants  get 
on  with  their  animal  and  plant  neighbors,  and  especially 
the  way  in  which  they  adjust  themselves  to  the  nature 
of  the  soil  and  climate  in  which  they  live.     Ecology,  in 
short,  discusses  the  relations  of  plants  to  their  surround- 
ings or  environment.     A  good  deal  of  what  has  been  said 
in  previous  chapters  about  such  topics  as  parasitic  plants, 
the  occurrence  of    winter   bud-scales,  the    movements  of 
leaves,   the    coating  of   hairs    on    stems    and  leaves,   the 
storage   of   water  in  epidermis-cells,  is    really  ecological 
botany,  although  it  is  not  so  designated  in  the  sections 
where  it  occurs. 

378.  Plant  Societies.  —  In  a  single  acre  of  woodland, 
of  marsh,  or  of  meadow,  there  will  usually  be  found  a 
large  number  of  species  of  plants.     One  species  may  be 
sufficiently  abundant  and  conspicuous  to  give  a  name  to 
the  whole  tract,  so  that  it  may,  for  instance,  be  recognized 
as  a  bit  of  birch  wood  or  of  cat-tail  swamp.     But  under 
the  birches  and  among  the  cat-tails  there  are  plants,  it  may 

307 


308  FOUNDATIONS   OF  BOTANY 

be,  of  a  hundred  other  kinds,  the  seed-plants  not  all  in 
bloom  at  any  one  season,  but  coming  along  in  succession 
from  earliest  spring  until  the  approach  of  winter.  The 
entire  set  of  plants  which  naturally  occupies  a  given  area 
of  land  under  somewhat  uniform  conditions  is  called  a 
plant  society. 

379.  Similar  Societies  due  to  Similar  Conditions.  —  As 
soon  as  the  young  botanist  begins  to  collect  plants  in  a  set 
of  localities  new  to  him,  he  discovers  that  his  old  acquaint- 
ances are  still  to  be  found  grouped  as  he  has  been  accus- 
tomed to  see  them.  The  rich  black  loam  of  a  wooded 
bank  a  hundred  miles  away  from  his  familiar  collecting 
ground  will  show  the  same  assemblage  of  slippery  elms 
and  lindens,  red  buds,  bladdernuts,  and  wahoos,  hepaticas, 
bloodroots,  Dutchman's  breeches,  trilliums,  pepper  root,  and 
wild  ginger,  with  a  multitude  of  later-blooming  herba- 
ceous plants,  that  he  has  learned  to  know  so  well.  The 
muddy  borders  of  ponds  from  Maine  to  Minnesota  and 
beyond  are  fringed  with  the  same  kinds  of  bur-reeds  and 
sedges,  set  with  water-plantain,  and  decorated  with  the 
soft  white  blossoms  of  the  arrowhead.  The  sand  dunes 
along  the  northern  Atlantic  coast  and  those  that  border 
Lake  Michigan  are  clothed  with  a  sparse  vegetation  which 
in  both  cases  includes  the  little  beach  plum,  such  coarse 
grasses  as  that  shown  in  Plate  I,  and  the  straggling  sea 
rocket.  Barnyards  and  waste  grounds  about  farm  build- 
ings from  Massachusetts  to  Missouri  contain  such  weeds 
as  the  dog  fennel,  the  low  mallow  ("cheeses"),  mother- 
wort,  catnip,  and  some  smartweeds. 

A  little  study  of  such  cases  soon  leads  one  to  the  con- 
clusion that  these  plant  societies  and  multitudes  of  others 


PLANT   SOCIETIES  309 

exist  because  all  the  plants  in  each  society  are  adapted  to 
their  special  environment.  Wherever  such  an  environment 
occurs  such  a  society  will  be  found  in  it,1  or,  if  not  already 
there,  will  flourish  when  introduced. 

380.  Similar  Species  replace  Each  Other Two  sets  of 

localities  alike  in  many  respects  but  unlike  in  some  points 
are  often  inhabited  by  different  species  of  the  same  genus. 
For  instance,  the  pine  barrens  of  New  England  and  the 
adjacent  states  are  commonly  covered  with  the  northern 
pitch  pine,  while  far  southward,  in  sandy  soil,  its  place 
is  taken  by  the  long-leaved  pine.  Along  streams  and 
swamps  northward  the  speckled  alder  is  generally  found, 
while  southward  the  smooth  alder  is  most  common.  In 
rich  woods  of  the  northeastern  United  States  the  painted 
trillium  and  the  erect  trillium  ("Benjamin,"  or  "squaw 
root ")  are  the  commonest  species,  while  far  south,  in  simi- 
lar localities,  the  sessile  trillium,  Underwood's  trillium, 
and  the  large-flowered  trillium  are  abundant. 

In  all  such  cases  —  and  they  are  very  numerous  —  we 
are  to  infer  that  the  genus  is  peculiarly  well  adapted  to 
some  especial  set  of  conditions,  as  sandy  soil,  brooksides,  or 
the  rich,  shaded  soil  of  woodlands.  But  the  more  northerly 
species  are  capable  of  enduring  the  severe  winters  and 
brief  summers  of  their  region,  while  the  more  southerly 
ones  perhaps  cannot  do  so.  The  relative  warmth  of  the 
climates  in  which  they  live  may  not  be  the  only  reason,  or 
even  the  principal  reason,  for  the  distribution  of  such 
plants  as  those  just  mentioned,  but  it  is  one  factor  at  any 
rate.  And  it  is  certain  that,  on  the  whole,  most  of  our 

1  That  is,  in  localities  not  separated  by  such  natural  barriers  as  seas,  high 
mountains,  or  deserts. 


310  FOUNDATIONS    OF   BOTANY 

native  and  thoroughly  naturalized  plants  are  growing 
under  what  is,  for  them,  the  best  environment,  since  they 
cannot  usually  be  made  to  exchange  places  with  each 
other.  If  a  square  mile  of  land  in  Louisiana  were  to  be 
planted  with  Minnesota  species,  and  a  square  mile  in 
Minnesota  with  Louisiana  species,  it  is  very  improbable 
that  either  tract,  if  left  to  itself,  would  long  retain  its 
artificial  flora.  To  this  rule  there  are,  however,  important 
exceptions  (see  Sect.  457). 

381.  Plant  Formations.  —  It  is  not  uncommon  to  find 
tracts   of  land   or  water  inhabited  by  great  numbers  of 
plants  of  the  same  species  so  as   almost  to  exclude   all 
other  plants  except  microscopic  cryptogams.     Ponds  and 
slowly  flowing  streams  are  often  filled  in  this  way  with 
the  water  hyacinth   or  the   American  lotus.      The  cane- 
brakes  of  the  south  and  the  wild  rice  swamps  along  north- 
ern lakes  and  rivers  are  other  examples  of  an  extremely 
simple  flora  spread  over  large  areas.     Prairies  not  infre- 
quently for  hundreds  of  square  miles  are  covered  mainly 
(not  entirely)   with  a  very  few  kinds  of  grasses.     Such 
assemblages  are  called  plant  formations  or  plant  colonies. 

382.  Ecological  Classification  of  Plants.  —  The  ordinary 
classification  of  plants,  as  set  forth  in  Chapter  XIX,  is 
based,  as  far  as  possible,  on  their  actual  relationships  to 
each  other.     But  when  plants  are  classified  ecologically 
they  are  grouped  according  to  their  relations  to  the  world 
about  them.     They  may,  therefore,   be  gathered  into  as 
many  (or  more  than  as  many)  different  groups  as  there 
are  important  factors  influencing  their  modes  of  life.    We 
may  classify  plants  as  light-loving  and  darkness-loving, 
as  requiring  free  oxygen,  and  not  requiring  it,  and  so  on. 


PLANT   SOCIETIES  311 

Indeed,  one  of  the  most  useful  classifications  of  bacteria, 
for  practical  purposes,  is  into  species  which  must  have  free 
oxygen,  that  is,  oxygen  not  chemically  combined  with  other 
substances,  in  order  to  grow  and  increase,  and  those  which 
can  live  without  it. 

The  most  important  consideration  in  classifying  seed- 
plants  on  ecological  grounds  is  based  on  their  require- 
ments in  regard  to  water.  Grouped  with  reference  to 
this  factor  in  their  life  all  plants  may  be  classed  as  : 

(1)  Hydrophytes,  or  water-loving  plants. 

(2)  Xerophytes,  or  drought-loving  (or   perhaps    drought-tolerating) 

plants. 

(3)  Mesopkytes,  or  plants  which  thrive  best  with  a  moderate  supply 

of  water. 

These  three  classes  do  not  fully  express  all  the  relations 
of  plants  to  the  water  supply,  so  two  others  are  found 
convenient. 

(4)  Tropophytes,  or  seasonal  plants  which  are  hydrophytes  during 

part  of  the  year  and  xerophytes  during  another  part.1 

(5)  Halophytes,  or  salt  marsh  plants  and  "alkali"  plants,  species 

which  can  nourish  in  a  very  saline  soil. 

383.  Difficulties  in  Ecological  Classification.  —  It  seems 
at  first  sight  a  simple  matter  to  group  plants  in  regard  to 
their  need  of  water.  There  can  be  no  difficulty  in  classi- 
fying as  hydrophytes  all  plants  like  the  bladderworts,  water 
cresses,  certain  mosses,  and  many  lower  spore-plants  which 
live  only  in  water.  Cactuses,  aloes,  and  similar  plants  are 
recognized  at  sight  as  xerophytes.  But  the  chief  difficulty 

1  The  plants  which  E.  Warming,  one  of  the  foremost  authorities,  classes  as 
mesophytes  are  many  of  them  grouped  by  another  great  authority,  A.  F.  W, 
Schiinper,  as  tropophytes. 


312 


FOUNDATIONS   OF   BOTANY 


is  in  dividing  mesophytes  from  the  other  two  classes,  into 
which  they  shade  by  indefinite  gradations.  In  order  to 
know  whether  the  plants  of  a  region  have  plenty  of  water 
or  not,  we  must  know  not  only  how  many  inches  of  yearly 
rainfall  there  are,  but  also  what  the  soil  is  like,  what  is 
the  temperature  of  the  soil  and  air,  whether  or  not  there 
are  dry  winds,  and  whether  there  are 
fogs  or  heavy  dews.  A  lichen  on  a 
bare  rock  may  be  living  almost  under 


FIG.  218.  —Aquatic  Plants  :  Pond-Lilies  with  Floating  Leaves  and 
Sedges  with  Aerial  Leaves. 

desert  conditions,  while  a  pitcher-plant  in  a  bog  near  by 
has  its  roots  in  standing  water  (or  in  ice)  nearly  all  the 
year  round. 

384.  Hydrophytes.  —  Some  of  these  are  herbaceous 
aquatic  plants,  like  the  duckweed,  the  pickerel-weed, 
the  pond-lily,  and  the  water-crowfoot ;  others,  such  as  the 
"calla"  (Richardia),  the  buckbean,  the  cat-tail,  and  the 
sweet  flag,  many  ferns,  mosses,  and  liverworts,  prefer 


PLANT   SOCIETIES 


313 


damp  air  and  soil.  All  of  them  transpire  freely,  and  many 
of  them  cannot  live  at  all  under  the  moisture  conditions 
which  suit  ordinary  plants. 

Some  aquatics  have  their  leaves  wholly  submerged, 
others,  such  as  the  duckweed  and  the  pond-lilies  (Fig.  218), 
have  them  floating,  and  still  others,  like  the  sedges  in  the 
same  picture,  have  their  leaves  freely  exposed  to  the  air. 
A  few  plants  have  both 
water-leaves  and  air-leaves 
(Fig.  219).  Some  aquatic 
plants  are  rooted  in  the  mud, 
while  others  have  no  roots 
at  all,  or,  like  the  duckweed, 
have  only  water-roots. 

The  leaves  of  land-plants 
in  very  rainy,  subtropical 
climates  are  exposed  to  the 
attacks  of  parasitic  spore- 
plants  which  flourish  on 
their  surfaces.  To  ward  off 
the  attacks  of  these  it  is 
necessary  to  keep  water  from  accumulating  on  the  surfaces 
of  the  leaves.  This  result  is  secured  by  a  waxy  deposit  on 
the  epidermis  and  also  by  the  slender  prolongation  to  drain 
off  surplus  water,  shown  in  Fig.  221.  That  this  slender 
leaf  tip  is  useful  in  the  way  suggested  is  proved  by  the  fact 
that  when  it  is  cut  squarely  off  the  leaf  no  longer  sheds 
water  freely. 

385,  Xerophytes.  —  A  xerophyte  is  a  plant  which  is 
capable  of  sustaining  life  with  a  very  scanty  supply  of 
water.  Since  the  first  plants  which  existed  were  aquatics 


FIG.  219.  —  Submerged  and  Aerial  Leaves 
of  a  European  Crowfoot  (Ranunculus 
Purs  hit).  The  leaf  with  thread-like 
divisions  is  the  submerged  one. 


314 


FOUNDATIONS   OF   BOTANY 


FIG.  220.  —  The  Duckweed,  a  Floating 
Aquatic  Plant. 


(Sect.  368),  we  must 
consider  that  xero- 
phytes  are  highly  spe- 
cialized and  modified 
forms  adapted  to  ex- 
tremely trying  condi- 
tions of  life.  A  typical 
xerophyte  is  one  which 
can  live  in  a  very  dry 
soil  in  a  nearly  rain- 
less region.  The  yucca 
in  Plate  VII  and  the 
melon-cactus  (Fig.  49) 


are  good  examples  of  such  plants. 
Less  extremely  xerophytic  are  plants 
like  the  date-palm  (Fig.  54),  which 
flourishes  in  the  oases  of  the  Sahara, 
where  the  soil  is  moist  from  the 
presence  of  springs,  though  rains  are 
almost  unknown,  or  the  houseleeks 
and  stonecrops  found  in  many  gar- 
dens, the  so-called  Spanish  moss 
(Plate  IV),  and  lichens  (Figs.  198, 
199),  all  of  which  grow  most  rapidly 
in  moist  air,  but  cling  to  bare  rocks 
and  trunks  of  trees,  from  which  they 
get  no  water.  A  xerophyte  must 
be  capable  of  storing  water  and  tran- 
spiring very  slowly,  like  cactuses, 
aloes,  stonecrops,  and  such  fleshy  plants 

1  Ficus  religiosa. 


FIG.  221.  — Leaf  of  an 
East  Indian  Fig  Tree,1 
with  a  Slender  Taper- 
ing Point  to  drain  off 
Water. 


FIG.  222.  —  A  Field  of  Prickly-Pear  Cactus  Plants  :  Xerophytes. 


316 


FOUNDATIONS   OF   BOTANY 


with  a  thick  epidermis,  or  else  it  must  be  able  to  revive 
after  being  thoroughly  dried.  A  few  seed-plants  and 
many  such  spore-plants  as  lichens,  Pleurococcus  (Sect. 
277),  yeast,  and  some  bacteria  (Sect.  263),  thrive  just  as 
well  after  remaining  for  some  months 
or  years  in  a  dried  condition  as  they 
did  before  drying.  A  good  illustration 
of  this  fact  as  regards  yeast  is  found  in 
the  use  of  dried  yeast  cakes,  made  of  a 
mixture  of  yeast  and  corn  meal.  These 
will  raise  dough  promptly  when  mixed 
with  it,  even  if  they  have  been  kept 
dry  for  a  year  or  more. 

386.  Roots  and  Stems  of  Xerophytic 
Seed-Plants.  —  Some  xerophytes  have 
roots  which  show  no  peculiarities  of 
form  or  structure,  but  many  make  special 
provision  for  storing  food  and  water  in 
their  roots.  Such  roots  are  fleshy  and 
often,  as  in  Harpagophytum  (Fig.  223), 
are  of  great  size  compared  with  the 
portion  of  the  plant  above  the  ground. 
Xerophytic  stems  are  frequently  very 
thick  in  proportion  to  their  length, 
sometimes  even  globular,  and  they 
commonly  contain  large  amounts  of  water.  In  leafless 
plants,  like  the  cacti,  the  surface  for  transpiration  is  much 
less  than  that  offered  by  leafy  plants.  Many  species  which 
bear  leaves  shed  most  of  them  at  the  beginning  of  the  dry 
season,  and  some  remain  thus  in  a  half  dormant  condi- 
tion for  long  periods,  as  is  the  case  with  many  Euphorbias 


FIG.  223.  —  Harpago- 
phytum, a  South 
African  Xerophyte. 


PLATE  VII.  —  Tree  Yucca  in  the  Mohave  Desert 


PLANT   SOCIETIES 


317 


(Fig.  245).  The  epidermis,  even  on  the  younger  portions 
of  the  stem,  is  highly  cutinized  (Fig.  121),  and  this  structure 
makes  any  evaporation  very  slow. 

387.  Leaves   of   Xerophytes.  —  In    regions    where    the 
greatest  dangers  to  vegetation  arise  from  long  droughts 
and  the  excessive  heat  of  the  sun,  the  leaves  of  plants 
usually  offer  much  less  surface  to  the  sun  and  air  than  is 
the  case  in  temper- 
ate climates.  Some- 
times the  blade  of 

the  leaf  is  absent 
and  the  expanded 
petiole  answers  the 
purpose  of  a  blade, 
or,  again,  foliage 
leaves  are  alto- 
gether lacking,  as  in  the  cactuses  (Fig.  222),  and  the  green 
outer  layers  of  the  stem  do  the  work  of  the  leaves* 

388.  Rolled-Up  Leaves.  —  Leaves  which  receive  but  a 
scanty  supply  of  water  are  often  protected  from  losing  it 
too  rapidly  by  being  rolled  up,  so  that  the  evaporating, 
i.e.,  stomata-containing,  surface  is  on  the  inside  of  the  roll. 
Sometimes,  as  in  the  crow-berry  (Fig.  224),  the  curled  con- 
dition is  permanent.     In  other  plants,  as  in  such  grasses 
as  Stipa  (Fig.  225),  and  in  Indian  corn,  the  leaf  rolls  up 
when  the  weather  is  very  dry  and  unrolls  again  when  it 
receives  a  better  supply  of  water. 

389.  Mesophytes.  —  A    mesophyte    is    a    plant    which 
thrives  best  with  a  moderate  supply  of  water.     The  great 
majority  of   the  wild    and   the  cultivated   plants  of   the 
United  States  are  mesophytes,  and  what  has  been  learned 


FIG.  224.  —  Cross-Section  of  Rolled-Up  Leaf  of  Craw- 
Berry  (Empetrum  nigrum).    (Magnified.) 


318  FOUNDATIONS   OF  BOTANY 

from  Part  I  of  this  book  about  the  forms,  structure,  and 
habits  of  ordinary  plants,  together  with  what  the  student's 
own  observation,  aside  from  the  study  of  botany,  has  taught 
him,  should  suffice  to  give  him  a  fair  idea  of  mesophytic 
plant  life. 

The  typical  mesophyte  of  the  northern  United  States  is 
an  annual,  since  most  of  our  larger  perennials  pass  the 
winter  in  a  xerophytic  condition,  to  avoid  destruction  by 
drying  up  during  the  long  period  when 
the  roots  can  absorb  little  or  no  water 


FIG.  225.  —  Cross-Section  of  Leaves  of  a  Grass,1  unrolled  for  Exposure  to 
Sunlight  and  rolled  up  to  prevent  Evaporation. 

r,  ridges  of  the  upper  epidermis,  with  many  stomata  on  their  surfaces ; 
e,  thick  lower  epidermis,  without  stomata. 

from  the  frozen  soil.  Our  evergreen  coniferous  trees, 
such  as  pines,  spruces,  cedars,  and  so  on,  have  leaves  of 
decidedly  xerophytic  structure.  So  also  do  such  ever- 
green shrubs  as  the  rhododendrons,  wintergreen,  arbutus, 
holly,  and  bearberry.  Our  deciduous  trees  and  shrubs  and 
most  perennial  herbs  are  tropophytes  (Sect.  390). 

390.  Tropophytes,  or  Seasonal  Plants.  —  Examples  of 
these  are  most  deciduous  trees  and  the  majority  of  the 
perennials  of  temperate  regions,  for  instance  oaks,  elms, 
birches  among  trees,  and  tulips,  crown  imperials,  lilies, 
hyacinths,  spring-beauties,  peonies,  dahlias,  and  potatoes 
among  herbs.  Such  plants  have  a  pretty  large  surface  for 

1  Stipa  capillata. 


PLANT   SOCIETIES 


319 


transpiration  during  the  summer  (or  in  regions  like  South- 
ern California  in  the  rainy  season)  and  a  greatly  reduced 
surface  during  the  winter  (or  the  dry  season). 

In  the  case  of  trees  the  reduction  of  surface  is  brought 
about  by  the  fall  of  the  leaves  (Sect.  186),  and  in  the  case 
of  herbaceous  perennials  it  is  secured  by  the  death  of  the 
green  stem  and  the  leaves,  so  that  only  a  compact  root, 
rootstock,  or  bulb  is  left  alive  underground.  That  is  to 
say,  the  perishable  or  annual  part  of  tropophytes  has  the 
characteristics  of  mesophytes  or  even  of  moisture-loving 
plants,  while  the  perennial  part  is  constructed  on  the  plan 
of  xerophytes. 

391.  Halophytes.  —  A  halophyte  is  a  plant  which  can 
thrive  in  a  soil  containing  much  common  salt  or  other 
saline  substances.  The  seaside  obviously  occurs  to  one  as 
the  region  of  halo- 
phytic  vegetation, 
but  many  inland 
areas  contain  halo- 
phytic  plants,  for 
instance  the  neigh- 
borhoods about  salt 
springs  and  the 
"  alkali "  lands  of 
the  southwest  and 
the  Pacific  Slope. 
The  presence  of  salt 
in  the  soil  renders 
absorption  of  the 
soil-water  comparatively  difficult,  since  osmosis  takes  place 
more  readily  between  ordinary  water  and  the  liquid 


Fio.  226.  —  The  Mangrove,  a  Halophytic  Tree  of 
Southern  Florida  and  the  Tropics. 


320  FOUNDATIONS    OF   BOTANY 

contents  of  root-hairs  and  young  roots  than  between  salt 
water  and  the  liquids  inside  the  root.  Halophytes,  there- 
fore, are  put  on  short  rations  as  regards  water,  even 
though  they  may  be  growing  in  a  watery  marsh.  Con- 
sequently halophytes  often  have  much  the  appearance  of 
fleshy  xerophytes  and  the  structure  of  xerophytes. 

The  mangrove  tree  (Fig.  226)  is  one  of  the  most  remark- 
able of  halophytes.  It  grows  in  shallow  water  along  the 
seashore  and  sends  out  many  aerial  roots  which  at  length 
find  their  way  down  into  the  salt  mud.  In  this  way  it 
collects  drift  material  and  gradually  extends  the  shore  line 
farther  out  to  sea. 

392.  Other  Kinds  of  Ecological  Classes.  —  It  is  easy  to 
class  plants  according  to  their  habits  in  many  other  regards 
than  according  to  their  relative  power  of  transpiration  (see 
Chapter  XXVI).  Only  one  other  kind  of  classification 
need,  however,  be  mentioned  in  this  chapter,  that  is,  the 
division  into  sun-loving  and  shade-loving  plants.  Even  in 
very  dense  forests  some  plants  will  be  found  growing  on 
the  soil  in  the  twilight  formed  by  the  shade  of  the  trees. 
Some  of  this  undergrowth  is  of  seed-plants,  and  there  are 
many  ferns  and  mosses  which  flourish  in  such  situations. 
Shade-plants  commonly  have  large  pale  leaves,  and  gener- 
ally (except  in  ferns)  the  leaves  are  not  much  cut  or 
lobed  (Fig.  227, 1).  Sun-loving  plants,  on  the  other  hand, 
usually  have  comparatively  little  leaf-surface,  and  the 
leaves  are  often  cut  into  narrow  divisions  (Fig.  227,  II). 
Apparently  the  broad  leaf-surfaces  in  the  one  class  are  to 
expose  many  green  cells  to  the  light  for  starch-making, 
while  in  the  other  class  the  slender  leaf-divisions  expose 
enough  assimilating  cells,  and  at  the  same  time  the 


PLANT   SOCIETIES 


321 


narrowness  of  the  division  permits  plenty  of  light  to 
penetrate  to  the  plant's  lower  leaves.  It  is  also,  doubt- 
less, much  easier  for  leaves  like  those  of  the  yarrow,  the 
dog  fennel,  the  tansy,  the  carrot,  and  their  like,  to  with- 
stand the  action  of 
severe  winds,  to 
which  they  are  often 
exposed,  than  it 
would  be  for  leaves 
like  those  of  the  jack- 
in-the-pulpit  (see 
Frontispiece),  the 
trilliums,  the  lily-of- 
the- valley,  and  simi- 
lar leaves. 

393.  Transition  of 
a  Plant  from  Shade 
Conditions  to  Sun 
Conditions.  --It  is 
characteristic  of 
many  kinds  of  forest 
trees  that  the  young 
seedlings  are  much 
more  tolerant  of 
dense  shade  than  the 
adult  trees  are. 
Sometimes  their  seeds  will  hardly  germinate  at  all  unless 
thoroughly  shaded,  and  the  young  trees  for  the  first  few 
years  flourish  best  in  the  shade.  Afterwards  most  trees 
need  a  good  deal  of  sunlight,  but  they  may  live  long 
with  a  scanty  supply  of  light.  The  red  spruce  sometimes 


i  ii 

FIG.  227.  —  I,  a  Shade-Plant  (Clintonia) ;  II,  a  Sun- 
Plant,  Dog  Fennel  (Maruta). 


322 


FOUNDATIONS   OF  BOTANY 


FlG.  228.  —  An  Epiphytic  Fern  (PI aty cerium)  on  a  Tree  Trunk. 

The  more  upright  leaves  next  the  trunk  of  the  tree  serve  to  collect  water 
and  to  accumulate  a  deposit  of  decaying  vegetable  matter,  while  the 
outer  leaves  serve  as  foliage  and  bear  spores. 


PLANT   SOCIETIES  323 

lingers  on  for  fifty  or  a  hundred  years,  reaching  meantime 
a  diameter  of  not  more  than  two  inches,  and  then,  on 
getting  more  light,  shoots  up  into  a  large  and  valuable 
timber  tree.1 

394.  Epiphytes.  —  It  is  even  easier  for  a  plant  to  secure 
enough  sunlight  in  a  forest  region  by  perching  itself  upon 
the  trunk  or  branches  of  a  tree  than  by  climbing,  as  our 
wild  grapevines  and  the  great  tropical  lianas  do.  There 
is  a  large  number  of  such  perched  plants,  or  epiphytes, 
embracing  species  of  many  different  groups  of  seed-plants 
and  of  spore-plants.  The  fern  shown  in  Fig.  228  is  a  good 
example  of  an  epiphyte.  Instances  among  seed-plants  are 
the  so-called  Florida  moss  (Plate  IV)  and  orchids  like 
those  in  Fig.  13. 

1  See  the  Primer  of  Forestry,  Part  I,  U.  S.  Department  of  Agriculture, 
1899,  pp.  33-35. 


CHAPTER   XXV 
BOTANICAL    GEOGRAPHY 

395.  Regions  of  Vegetation.  —  The  earth's  surface  (that 
of  the  land)  has  been  described  by  one  of  the  greatest  of 
geographical  botanists1  as  divided  into  twenty-four  regions 
of  vegetation.     This  classification  takes  account  of  all  the 
principal  continental  areas  which  have  a  characteristic  set 
of  plants  of  their  own,  as  well  as  of  the  most  important 
islands.     But  a  simpler  arrangement  is  to  consider  the 
plant  life  of  the  earth  as  distributed  among  the  following 

regions : 

1.  The  tropical  zone. 

2.  The  temperate  zones. 

3.  The  arctic  zones. 

4.  Mountain-heights. 

5.  Bodies  of  water. 

Any  good  geography  gives  some  account  of  at  least  the 
land  vegetation  of  the  earth.  It  is  necessary  in  the  pres- 
ent chapter  only  to  point  out  a  few  of  the  most  important 
characteristics  of  the  plants  of  the  zones  and  other  areas 
mentioned  above  and  to  give  some  reasons  why  the  plant 
population  of  each  has  its  special  characteristics. 

396.  Tropical  Vegetation.  —  Within  the  tropics  two  of 
the  great  factors  of  plant  life  and  growth,  namely,  light 
and  heat,  are  found  in  a  higher  degree  than   elsewhere 
on  the  earth.     Moisture,  the  third  requisite,  is  in  some 

1  A.  Grisebach. 
324 


BOTANICAL   GEOGRAPHY  325 

regions  very  abundant  (over  sixteen  feet  of  rainfall  in  a 
year)  or  sometimes,  in  desert  areas,  almost  lacking.  We 
find  here,  accordingly,  the  greatest  extremes  in  amount 
of  vegetation,  from  the  bare  sands  or  rocks  of  the  Sahara 
desert  (Fig.  229)  to  the  densely  wooded  basin  of  the 
Kongo  and  of  the  Amazon.  Xerophytic  plants,  many  of 
them  with  extremely  complete  adaptations  for  supporting 
life  for  long  periods  without  water,  are  characteristic  of 
tropical  deserts,  while  many  of  the  most  decided  hydro- 
phytes among  land-plants  are  found  in  the  dripping  sub- 


FIG.  229.  — Hills  of  Drifted  Sand  in  the  Sahara. 

tropical  forest  interiors.  Throughout  a  large  part  of  the 
zone,  reaching  five  degrees  each  way  from  the  equator, 
there  are  daily  rains  the  year  round. 

397.  Vegetation  of  the  Temperate  Zones.  —  We  are  all 
familiar  in  a  general  way  with  the  nature  of  the  plant 
life  of  the  north  temperate  zone ;  that  of  the  south 
temperate  is  in  most  ways  similar  to  our  own.  Most  of 
the  annuals  and  biennials  are  of  a  medium  type,  not 
decided  xerophytes  nor  hydrophytes,  and  the  perennials 
are  mainly  tropophytes.  There  are  no  desert  areas  so 
large  or  so  nearly  destitute  of  plants  as  those  found  in 
subtropical  regions,  neither  are  there  any  such  luxuriant 


326 


FOUNDATIONS   OF   BOTANY 


growths  as  occur  in  the  rainy  forest  regions  of  the  tropics. 
On  the  other  hand,  the  largest  trees  on  earth,  the  "  big 
trees,"  or  Sequoias  (Fig.  32),  occur  in  the  temperate  por- 
tion of  North  America,  along  the  Sierra  Nevada,  and 
the  taller,  though  less  bulky,  gum  trees  (Eucalyptus)  of 
Australia  grow  in  a  warm  temperate  region. 

398.  Temperate  Plant  Societies  due  to  Special  Conditions 
of  Soil.  —  Even  where  the  climate 
is  a  moderate  one  as  regards  tem- 
perature and  rainfall,  peculiar 
soils  may  cause  the  assemblage 
of  exceptional  plant  societies. 
Some  of  the  most  notable  of 
such  societies  in  temperate  North 
America  are  those  of  the  salt 
marshes,  the  sand  dunes,  and  the 
peat  bogs. 

In  salt  marshes  the  water  sup- 
ply is  abundant,  but  plants  do  not 
readily  absorb  salt  water  by  their 
roots,  so  that  the  plants  which 
grow  in  salt  marshes  usually  have 
something  of  the  structure  and  appearance  of  xerophytes. 
Some  of  them  are  fleshy  (Fig.  230),  and  some  species  are 
practically  leafless. 

Sand  dunes,  whether  along  the  seacoast  or  near  the 
great  lakes,  offer  a  scanty  water  supply  to  the  roots  dur- 
ing much  of  the  year,  and  the  soil-water  contains  less  of 
the  raw  materials  for  plant  food  than  is  offered  by  that 
of  ordinary  soils.  Many  grasses  thrive,  however,  in  these 
shifting  sands  (Plate  I),  and  some,  like  the  beach-grass 


FIG.  230.  — A  Halophytic  Plant 
(Salicornia). 


BOTANICAL   GEOGRAPHY 


327 


(Ammophila)  of  the  Atlantic  coast  and  the  great  lakes, 
will  continue  to  grow  upward  as  the  sand  is  piled  about 


ifill 


w 


them  by  the  winds  until  they 
have  risen  to  a  level  of  a 
hundred  feet  above  the  start- 
ing point. 

Peat    bogs    are    especially 
characterized  by  the  predominance  of 
the  peat  mosses  (Fig.  231)  from  which 
they  take  their  name. 
These  plants  and  the  others  which  associ- 
ate with  them  are  mostly  hydrophytes,  living 
usually  with  a  considerable  portion  of  the 
plant    continually   submerged   in   the    bog 
water.      The  water  of  such  bogs  contains 
little  mineral  matter  and  only  a  very  scanty 
supply  of  nitrogen,  in  the  form  of  nitrates 
dissolved  in  it.     The  bog-plants,  therefore, 
must  either  get  on  with  an  exceptionally 
small  supply  of  nitrogen  or  they  must  get 
it  from  an  unusual  source.    The  peat  mosses 
adopt  the  former  alternative,  while  the  sun 
dews   (Fig.   238),   the    pitcher-plants    (Fig. 
237),  and  some  other  species  adopt  the  latter  and 
derive  their  nitrogen  supply  largely  from  insects 
which  they  catch,  kill,  and  digest. 

399,  Arctic  Vegetation.  —  The  seed-plants  of  the 
arctic  flora  are  mostly  perennials,  never  trees. 
By  the  large  bulk  of  the  un(iergroun(j  portion 

as   compared  with  that  of  the  part  above   ground,  they 
are  adapted  to  a  climate  in  which  they  must  lie  dormant 


FIG.  23i. 
Peat  MOSS 


328  FOUNDATIONS   OF  BOTANY 

for  not  less  than  nine  months  of  the  year.  The  flowers 
are  often  showy  and  appear  very  quickly  after  the  brief 
summer  begins.  Mosses  and  lichens  are  abundant,  —  the 
latter  of  economical  importance  because  they  furnish  a 
considerable  part  of  the  food  of  reindeer. 

400.    Mountain  or  Alpine  Vegetation.  —  In  a  general  way 
the  effect  of  ascending  a  mountain,  so  far  as  vegetation  is 


FIG.  232.  —  A  Plant  of  Arctic  Willow.     (About  natural  size.) 

concerned,  is  like  that  of  traveling  into  colder  regions. 
It  was  long  ago  suggested,  in  regard  to  Mount  Ararat, 
that  on  ascending  it  one  traversed  first  an  Armenian,  then 
a  South  European,  then  a  French,  then  a  Scandinavian, 
and  finally  an  arctic  flora.  Up  to  a  certain  height,  which 
varies  in  different  latitudes,  the  slopes  of  mountains  are 
very  commonly  forest-covered.  The  altitude  up  to  which 
trees  can  grow  (or  as  it  is  commonly  called  in  this  country 
the  "  timber  line  ")  is  somewhat  over  twelve  thousand  feet 


BOTANICAL  GEOGRAPHY 


329 


in  the  equatorial  Andes  and  lessens  in  higher  latitudes  as 
one  goes  either  way  from  the  equator.  In  the  White 
Mountains,  for  instance,  the  timber  line  only  rises  to  about 
four  thousand  five  hundred  feet.  The  seed-plants  of  alpine 
regions  in  all  parts  of  the  earth  have  a  peculiar  and  charac- 
teristic appearance.  It  is  easiest  to  show  how  such  plants 
differ  from  those  of  the  same  species  as  they  look  when 


FIG.  233.  —  Trees  near  the  Timber  Line  on  the  Slope  of  Pikes  Peak. 

growing  in  ordinary  situations  by  reference  to  the  plants 
themselves  or  to  good  pictures  of  them  (see  Fig.  285). 
The  differences  between  alpine  and  non-alpine  plants  of 
the  same  or  closely  related  species  have  been  summed  up 
as  follows : l 

"The  alpine  individuals  have  shorter  stems,  smaller  leaves, 
more  strongly  developed  roots,  equally  large  or  somewhat 
larger  and  usually  somewhat  more  deeply  colored  flowers, 
and  their  whole  structure  is  drought-loving  (xerophilous)." 

i  By  A.  F.  W.  Schimper. 


830 


FOUNDATIONS   OF  BOTANY 


FIG.  234.  —  Decrease  in  Size  of  Trees  at  High  Elevations  (Canadian  Kockies). 

Trees  at  great  elevations  become  much  gnarled  and 
stunted,  as  their  growth  is  necessarily  very  slow  (Fig. 
233).  The  gradual  diminution  of  the  height  of  the 


BOTANICAL   GEOGRAPHY 


331 


trees  on  ascending  a  mountain  is  well  shown  in  Fig.  234. 
The  treeless  character  of  the  mountain  summit  is  also 
plain.1 

Recent  experiments  have  shown  that  many  ordinary 
plants  promptly  take  on  alpine  characteristics  when  they 
are  transferred  to  moderate  heights  on  mountains.  For 
instance,  a  rather 
commonly  culti- 
vated sunflower,2 
when  planted  at  a 
height  of  about  six 
thousand  five  hun- 
dred  feet,  instead 
of  having  a  tall 
leafy  stem  pro- 
duces a  rosette  of 
very  hairy  leaves 
lying  close  to  the 
ground,  thus  be- 
coming almost  un- 
recognizable as  a 
sunflower.  The 
change  was  even 
greater  than  that 
shown  in  the  rock 
rose  (Fig.  235)  cultivated  by  the  same  experimenter.  The 
peculiarities  of  alpine  plants  appear  to  be  due  mainly  to 
the  intense  light  which  they  receive  during  the  daytime, 

1  Part  of  the  diminution  is  only  apparent,  —  the  effect  of  distance,  — but  the 
growth  at  the  highest  levels  is  often  less  than  waist  high. 

2  Helianthus  tuberosus,  the  so-called  Jerusalem  artichoke. 


FIG.  235.  —  Two  Plants  of  Rock  Rose  (Helianthemum). 

(Both  drawn  to  the  same  scale.) 
A,  low  ground  form  ;  B,  alpine  form. 


332  FOUNDATIONS   OF  BOTANY 

to  the  strongly  drying  character  of  the  air  in  which  they 
grow  (due  partly  to  its  rarefaction),  and  to  the  low  temper- 
ature which  they  must  endure  every  night. 

401.  Aquatic  Vegetation.  —  Plants  which  live  wholly  in 
water  often  need  a  less  complicated  system  of  organs  than 
land-plants.  True  roots  may  be  dispensed  with  altogether, 
as  in  many  seaweeds,  in  most  fresh-water  algae,  and  in 
some  seed-plants.  A  few  such  plants  have  mere  hold- 
fasts that  keep  them  from  drifting  with  the  waves  or  the 
current.  Sometimes  roots  may,  as  in  the  duckweeds 
(Fig.  220),  serve  the  purpose  of  a  keel  and  keep  the 
flat,  expanded  part  of  the  plant  from  turning  bottom  up. 
The  tissues  that  give  strength  to  the  stems  and  leaves  of 
land-plants  are  not  usually  much  developed  in  submerged 
aquatics,  since  the  water  supports  the  weight  of  such 
plants.  In  some  algae,  as  the  common  rockweed  or  blad- 
der-wrack (Fig.  183),  the  weight  of  the  plant  is  admi- 
rably buoyed  up  by  large  air-bladders.  Transpiration  is 
done  away  with,  and  whatever  carbonic  acid  gas  or  oxygen 
is  absorbed  or  given  off  passes  directly  through  the  cell- 
walls  into  the  interiors  of  the  cells.  Generally  water- 
plants  do  not  reach  any  great  size,  but  some  species  are 
the  longest  of  known  plants,  Macrocystis,  the  great  kelp 
of  the  Pacific  Ocean,  attaining,  it  is  said,  the  length  of  a 
thousand  feet  or  more.  In  spite  of  the  moderate  size  of 
most  algae  the  total  bulk  in  the  various  oceans  must  be 
extremely  large.  The  Sargasso  Sea  alone,  in  the  Atlantic 
Ocean,  reaches  most  of  the  way  from  the  Bahamas  to  the 
Azores  and  extends  over  seventeen  degrees  of  latitude. 
The  whole  area  is  occupied  by  a  nearly  compact  mass  of 
floating  seaweed. 


BOTANICAL  GEOGKAPHY  333 

Besides  the  comparatively  well-known  and  readily  seen 
larger  algse  there  is  a  great  amount  of  vegetation  floating 
in  what  is  known  as  the  plankton.  This  is  a  mass  of 
microscopic  animals  and  plants,  found  floating  scum-like 
or  submerged  in  fresh  and  in  salt  water  and  often  accu- 
mulated in  great  quantities  near  shores,  to  which  it  is 
swept  by  the  action  of  the  wind  and  waves  and  currents. 
Much  of  the  plant  life  of  the  plankton,  both  of  fresh  and 
of  salt  water,  often  consists  of  the  flinty-shelled  one-celled 
microscopic  algae  known  as  diatoms  (Fig.  176). 

402.  Botanical  Geography  of  the  United  States.  —  All  of 
the  continuous  territory  of  the  United  States  l  lies  in  the 
north  temperate  zone.  There  is  material  for  a  large  vol- 
ume in  the  discussion  of  the  distribution  of  plants  over 
our  territory  in  this  continent  alone,  but  it  is  possible  to 
sum  up  a  mere  outline  of  the  matter  in  a  very  few  words. 
Excluding  the  floras  of  many  single  mountains  and  moun- 
tain ranges,  the  land  surface  of  the  country  may  for  botan- 
ical purposes  be  divided  into  four  great  areas,  as  follows : 

1.  TJie  Forest  Region.  —  This  occupies  the  eastern  and 
central  portion  of  the  United  States.     It  is  bounded  on 
the  west  by  an  irregular  line,  most  of  which  lies  to  the 
eastward  of  the  hundredth  meridian.     In  some  places  this 
forest  boundary  extends  eastward  across  the  Mississippi 
River,  while    in    others    it  recedes    from  the    river   five 
hundred  miles  or  more  to  the  westward. 

2.  The  Great  Plains  Region.  —  This  extends  westward 
from    the    region  above  named  to   the   Rocky  Mountain 
Plateau. 

1  That  is,  not  counting  in  Alaska,  our  West  Indian  possessions,  the  Sand- 
wich Islands,  or  the  Philippines. 


334  FOUNDATIONS   OF   BOTANY 

3.  The  Pacific  Highland  Region.  —  This  includes    the 
Rocky  Mountains,   the  Sierra  Nevada,   and  the    various 
plateaus  between  them. 

4.  The  Pacific  Slope.  —  This  extends  from  the  Cascade 
Range  and  the  Sierra  Nevada  to  the  sea. 

403,  Characteristics  of  the  Four  Regions.  —  The  forest 
region  is  mainly  remarkable  for  its  great  variety  of  hard- 
wood trees,  of  which  it  contains  a  larger  number  of 
useful  species  than  any  equal  area  of  the  earth  with  a 
temperate  climate.  In  the  northeasterly  portion  and  in 
much  of  the  southerly  portion  there  are  extensive  forests 
of  the  cone-bearing  evergreens,  such  as  pines,  spruces, 
hemlocks,  and  cedars.  The  vegetation  is  in  general 
such  as  thrives  in  medium  conditions  as  regards  heat 
and  rainfall. 

The  plains  region  is  largely  covered  with  grasses,  many 
of  them  xerophytes.  Some  of  the  most  characteristic  plants 
associated  with  the  grasses  are  Compositse,  such  as  sun- 
flowers, rosin-weeds  (Sttphium),  cone-flowers,  gum-weeds 
(G-rindelia),  and  blazing-stars  (Liatris). 

The  Pacific  highland  region  includes  a  very  great  vari- 
ety of  plant  societies,  from  the  heavily  wooded  mountain 
slopes  and  valleys  to  high  sterile  plains  which  are  almost 
deserts.  Cone-bearing  evergreen  trees  are  very  character- 
istic of  the  forests.  Great  numbers  of  alpine  species  of 
herbs  and  shrubs  are  found  on  the  mountains  at  aud  above 
the  timber  line.  In  the  alkali  regions,  where  the  soil  is 
too  full  of  mineral  salts  to  permit  ordinary  plants  to  grow, 
many  kinds  of  xerophytes,  such  as  the  salty  sage  (Atriplex] 
and  the  greasewood  (Sarcobatuz),  occur.  In  the  southern 
portion  cactuses  abound. 


•: 


BOTANICAL  GEOGRAPHY  335 

The  Pacific  Slope  is  characterized  by  cone-bearing  ever- 
greens in  great  abundance  in  the  mountains  and  along  the 
foothills.  Chief  among  these  in  point  of  size  are  the  red- 
woods and  the  ubig  trees"  (Sequoias)  (Fig.  32).  Oaks 
are  represented  by  a  good  many  species,  several  of  them 
evergreen.  There  are  many  xerophytes,  some  of  them 
characteristic  of  alkali  regions;  and  in  Southern  California, 
on  account  of  the  long  dry  season,  plants  with  large  roots 
or  rootstocks  and  bulb-bearing  plants  (many  of  them 
belonging  to  the  lily  family)  are  abundant.  The  tree 
yucca  (Plate  VII)  is  one  of  the  largest  and  most  inter- 
esting xerophytic  plants  of  North  America. 


CHAPTER   XXVI 

PARASITES,    ENSLAVED    PLANTS,    MESSMATES, 
CARNIVOROUS    PLANTS 

404.  Parasites.  —  A  little  was  said  in  Chapter  IV  about 
parasitic  plants,  and  the  life  history  of  one  of  them,  the 
dodder,  was  briefly  outlined  ;  another,  the  wheat  rust,  was 
discussed  in   Sects.  310—313.     A  parasitic  plant  is   one 
which  draws  its  supply  of  food  partially  or  wholly  from 
another  living  plant  or  animal  known  as  the  host.     Some 
parasites   are   seed-plants,   but  a    far  greater  number  of 
species  are  spore-plants. 

405.  Half-Parasitic  Seed-Plants.  —  Half-parasites  or  par- 
tial parasites  are  those  which  take  a  portion  of  their  food  (or 
of  raw  materials  to  make  food)  from  their  host  and  manu- 
facture the  rest  for  themselves.     Usually  they  take  mainly 
the  newly  absorbed  soil-water  from  the  host  and  do  their 
own  starch-making  by  combining  the  carbonic  acid  gas, 
which  they  absorb  through  their  leaves,  with  the  water 
stolen  by  the  parasitic  roots  or  haustoria  imbedded  in  the 
wood  of  the  host.     Evidently  the  needed  water  may  just 
as  well  be  taken  from  the  underground  parts  of  the  host 
as  from  the  upper  portions,  and  accordingly  many  half- 
parasites  are  parasitic  on  roots.     This  is  the  case  with 
many  of  the  beautiful  false  foxgloves  (Gerardia),  with  the 
painted-cup  (Caetillea),  and  some  species  of  bastard  toad- 
flax ( Oomandra) ;  see  Flora.     Usually  these  root-parasites 
are  not  recognized  by  non-botanical  people  as  parasites  at 

336 


PLATE  IX.  —  A  Cottonwood  covered  with  Mistletoe 


PARASITES  33  T 

all,  but  in  Germany  a  species  common  in  grain  fields  l  and 
the  eyebright,  which  abounds  in  grass  fields,  are  respectively 
known  as  "hunger"  and  " milk-thief,"  from  the  injury 
they  do  to  the  plants  on  which  they  fasten  themselves. 
The  mistletoe  is  a  familiar  example  of  a  half-parasite, 
which  roots  on  branches  (Plate  IX).  Among  the  scanty 
belts  of  cottonwood  trees  along  streams  in  New  Mexico  it 
is  necessary  to  lop  off  the  mistletoe  every  year  to  give  the 
tree  any  chance  to  grow.  Half-parasites  may  be  known 
from  plants  that  are  fully  parasitic  by  having  green  or 
greenish  foliage,  while  complete  parasites  have  no  chloro- 
phyll and  so  are  not  at  all  green. 

406.  Wholly  Parasitic  Seed-Plants.  —  These  are  so  nearly 
destitute  of  the  power  of  assimilation  that  they  must  rob 
other  plants  of  all  needed  food  or  die  of  starvation.    Some, 
like  the  cancer-root  (see  Flora),  are  root-parasites ;  others, 
like  the  dodder,  are  parasitic  on  stems  above  ground.     The 
most  dependent  species  of  all,  such  as  the  flax-dodder,  can 
live  on  only  one  kind  of  host,  while  the  coarse  orange- 
stemmed  dodder,2  which  is  common  all  over  the  central 
and  the  northeastern  states,  grows  freely  on  many  kinds 
of  plants,  from  golden-rods  to  willows. 

407.  Parasitic  Cryptogams.  —  The  wheat  rust  (Sect.  310) 
affords  an  excellent   example  of   the    relations    between 
parasitic  fungi  and  their  hosts.     The  illustration  showing 
the  potato  blight  escaping  from  a  stoma  of  the  potato  leaf 
(Fig.  191)   shows  plainly  one  way  in  which  a  microscopic 
parasite  finds  its  way  out  of  the  tissues  of  the  host-plant 
to  ripen  and  scatter  its  spores. 

1  Alectorolophus  hirsutus, 
«  Cwcuta  Qronovii, 


338  FOUNDATIONS   OF  BOTANY 

Perhaps  the  most  interesting,  certainly  to  us  the  most 
practically  important,  cases  of  parasitism  are  those  in 
which  the  bodies  of  animals,  and  especially  of  men,  are 
attacked  by  parasitic  plants.  Bacilli  and  other  bacteria 
of  many  species  (Sect.  263)  are  among  the  commonest 
parasites  which  use  the  bodies  of  animals  as  hosts,  and 
two  or  three  examples  will  serve  to  illustrate  how  they 
find  a  lodgment  in  the  host. 

Rich  garden  soil,  the  dust  of  stables,  and  a  good  many 
other  sources  often  contain  immense  numbers  of  a  bacil- 
lus1 which  causes  lockjaw.  A  man  in  cleaning  harness 
scratches  his  hand  with  a  buckle,  introduces  the  bacilli 
into  his  system,  and  is  soon  taken  with  an  attack  of  lock- 
jaw. Sewage  water  often  swarms  with  the  bacilli  of 
typhoid  fever2  (Fig.  174).  The  people  in  a  city  drink 
unfiltered  water  from  a  river  into  which  sewage  has  been 
allowed  to  run  higher  up  stream,  the  bacilli  multiply  at  a 
rapid  rate  in  the  intestines  of  those  who  have  drunk  the 
water,  and  many  of  them  are  taken  sick  with  typhoid 
fever.  The  phlegm  expectorated  by  consumptive  patients 
is  full  of  the  consumption  bacillus ; 3  this  phlegm  becomes 
dried  up  on  floors,  streets,  or  sidewalks,  it  is  breathed  by 
every  one  in  the  form  of  fine  dust,  and  in  the  lungs  of 
many  who  breathe  it  colonies  of  the  bacillus  are  formed 
and  the  disease  (consumption)  becomes  established  in 
these  persons. 

408.  Enslaved  Plants.  —  Cases  in  which  one  kind  of 
plant  is  useful  in  procuring  food  (or  the  raw  materials 
of  food)  for  another  kind  are  quite  common. 

The  relations  on  which  algse  and  fungi  live  together  in 

1  Bacillus  tetani.  2  Bacillus  typhi.  'Bacillus  tuberculosis. 


ENSLAVED   PLANTS 


339 


the  form  of  lichens  have  already  been  described  (Sect.  331). 
It  is  not  correct  to  describe  the  condition  of  such  algae 
as  slavery  if  the  term  is  meant  to  imply  that  they  derive 
no  benefit  from  the  association.  Perhaps  serfdom  is  a 


FIG.  236.  —Boots  of  Red  Clover  with  Tubercles. 

I,  sections  of  ascending  branches  ;  6,  enlarged  base  of  stem  ;  t,  root-tubercles 
containing  bacteria. 


more  suitable  word,  though  it  is  not  the  term  used  by 
botanists.  At  all  events,  the  alga  is  enclosed  within  a 
network  of  fungus  hyphse  from  which  it  cannot  readily 
escape,  and  there  does  most  of  the  work  of  the  lichen, 
including  all  of  the  manufacture  of  food  from  carbon 
dioxide. 


340 


FOUNDATIONS   OF  BOTANY 


409.  Messmates.1  —  Plants  of  very  diverse  character, 
which  live  most  intimately  together  to  the  advantage  of 
both  parties,  may  be  called  messmates,  since  in  some  fashion 

or  other  they  divide  the 
food  supply  between 
them. 

Bacteria  live  in  col- 
onies enclosed  in  root- 
tubercles  on  the  roots  of 
certain  plants,  for  in- 
stance, beans,  peas,  lu- 
pines, vetches,  and  clover 
(Fig.  236),  and  render 
the  greatest  service  to 
the  plant  to  which  the 
roots  belong,  from  which 
they  also  derive  food  and 
shelter.  Such  plants  do 
not  develop  root- 
tubercles  and  will  not 
grow  well  in  sterilized 
soil,  that  is,  soil  in  which 
the  bacteria  have  been 

FIG.  237.  — Common  Pitcher-Plant.2  killed   by  baking.       It  is 

found  that  the  bacteria 
serve  to  change  nitrogen 
taken  from  the  air  of  the  soil  into  nitric  acid,  which  is  a 
most  important  ingredient  in  the  manufacture  of  proteids. 
Many  trees,  for  example,  oaks,  beeches,  and  the  cone- 

1  This  term  is  borrowed  from  the  zoologists  as  a  much  simpler  one  than 
symbionts  to  express  the  relation  variously  known  as  symbiosis,  commensalism, 
or  mutualism.  2  Sarracenia  purpurea. 


At  the  right  one  of  the  pitcher-like  leaves  is 
shown  in  cross-section. 


INSECTIVOROUS   PLANTS 


341 


FIG.  238.  —  Sundew  (Drosera  rotundifolia). 

bearing  evergreens,  and  a  considerable  number  of  herbaceous 
plants,  such  as  the  Indian  pipe  (Monotropa,  Plate  V), 
are  covered  with  a  growth  of  fungus  hyphae  (Sect.  307). 


342 


FOUNDATIONS   OF  BOTANY 


FIG.  239.  — Blade  of  Leaf 
of  Sundew.  (Somewhat 
magnified.) 


This  growth  completely  surrounds  the 
young,  active  tips  of  all  the  roots  and 
the  threads  of  the  mykorhiza,  as  it  is 
called,  seem  to  do  the  work  of  root- 
hairs. 

410.  Carnivorous  Plants.  —  In  the 
ordinary  pitcher-plants  (Fig.  237)  the 
leaf  appears  in  the  shape  of  a  more  or 
less  hooded  pitcher.  These  pitchers 
are  usually  partly  filled  with  water, 
and  in  this  water  very  many  drowned 
and  decaying  insects  are  commonly 
to  be  found.  The  insects  have  flown 
or  crawled  into  the  pitcher,  and,  once  inside,  have  been 
unable  to  escape  on  account  of  the  dense  growth  of  bristly 
hairs  about  the  mouth,  all  pointing  inward  and  downward. 
How  much  the  com- 
mon American  pitcher- 
plants  depend  for 
nourishment  on  the 
drowned  insects  in  the 
pitchers  is  not  defi- 
nitely known,  but  it  is 
certain  that  some  of 
the  tropical  species  re- 
quire such  food.1 

FIG.  240.  —  Leaves  of  Sundew.    (Somewhat 

In  other  rather  com-  magnified.) 

mon    plants,     the    SUn-      The  one  at  the  left  has  all  its  tentacles  closed 
-.  over  captured  prey  ;  the  one  at  the  right  has 

6WS,     insects     are          only  half  of  them  thus  closed. 

1  Where  the  Sarracenia  is  abundant  it  will  be  found  interesting  and  profit- 
able to  make  a  careful  class  study  of  its  leaves.  See  Geddes,  Chapters  in 
Modern  Botany,  Chapters  I  and  II. 


INSECTIVOROUS   PLANTS 


343 


caught  by  a  sticky  secretion  which  proceeds  from  hairs  on 
the  leaves.  In  one  of  the  commonest  sundews  the  leaves 
consist  of  a  roundish  blade,  borne  on  a  moderately  long 
petiole.  On  the  inner  surface  and  round  the  margin  of 
the  blade  (Fig.  239)  are  borne  a  considerable  number  of 
short  bristles,  each  ter- 
minating in  a  knob  which 
is  covered  with  a  clear, 
sticky  liquid.  When  a 
small  insect  touches  one 
of  the  sticky  knobs,  he 
is  held  fast  and  the  hairs 
at  once  begin  to  close 
over  him,  as  shown  in 
Fig.  240.  Here  he  soon 
dies  and  then  usually  re- 
mains for  many  days, 
while  the  leaf  pours  out 
a  juice  by  which  the 
soluble  parts  of  the  insect 
are  digested.  The  liquid 
containing  the  digested 
portions  is  then  absorbed 

FIG.  241.  —  Venus  Flytrap. 

by  the  leaf  and  contrib- 
utes an  important  part  of  the  nourishment  of  the  plant, 
while  the  undigested  fragments,  such  as  legs,  wing-cases, 
and  so  on,  remain  on  the  surface  of  the  leaf  or  may  drop 
off  after  the  hairs  let  go  their  hold  on  the  captive  insect. 

In  the  Venus  flytrap,  which  grows  in  the  sandy  regions 
of  eastern  North  Carolina,  the  mechanism  for  catching 
insects  is  still  more  remarkable.  The  leaves,  as  shown  in 


344  FOUNDATIONS   OF  BOTANY 

Fig.  241,  terminate  in  a  hinged  portion  which  is  surrounded 
by  a  fringe  of  stiff  bristles.  On  the  inside  of  each  half 
of  the  trap  grow  three  short  hairs.  The  trap  is  so  sensi- 
tive that  when  these  hairs  are  touched  it  closes  with  a  jerk 
and  very  generally  succeeds  in  capturing  the  fly  or  other 
insect  which  has  sprung  it.  The  imprisoned  insect  then 
dies  and  is  digested,  somewhat  as  in  the  case  of  those 
caught  by  the  sundew,  after  which  the  trap  reopens  and 
is  ready  for  fresh  captures. 

411.  Object  of  catching  Animal  Food.  —  It  is  easy  to 
understand  why  a  good  many  kinds  of  plants  have  taken 
to  catching  insects  and  absorbing  the  digested  products. 
Carnivorous,  or  flesh-eating,  plants  belong  usually  to  one 
of  two  classes  as  regards  their  place  of  growth  ;  they  are 
bog-plants  or  air-plants.  In  either  case  their  roots  find  it 
difficult  to  secure  much  nitrogen-containing  food,  that  is, 
much  food  out  of  which  proteid  material  can  be  built  up. 
Animal  food,  being  itself  largely  proteid,  is  admirably 
adapted  to  nourish  the  growing  parts  of  plants,  and  those 
which  could  develop  insect-catching  powers  would  stand 
a  far  better  chance  to  exist  as  air-plants  or  in  the  thin, 
watery  soil  of  bogs  than  plants  which  had  acquired  no 
such  resources. 


CHAPTER   XXVII 
HOW   PLANTS    PROTECT    THEMSELVES    FROM   ANIMALS 

412.  Destruction  by  Animals.  —  All  animals  are  sup- 
ported directly  or  indirectly  by  plants.     In  some  cases  the 
animal  secures  its  food  without  much  damaging  the  plant 
on  which  it  feeds.     Browsing  on  the  lower  branches  of  a 
tree  may  do  it  little  injury,  and  grazing  animals,  if  not 
numerous,  may  not  seriously  harm  the  pasture  on  which 
they  feed.     Fruit-eating  animals  may  even  be  of  much 
service  by  dispersing  seeds  (Sect.  453).     But  seed-eating 
birds  and  quadrupeds,  animals  which,  like  the  hog,  dig  up 
fleshy  roots,  rootstocks,   tubers  or   bulbs,  and  eat  them, 
or  animals  which,  like,  the  sheep,  graze  so  closely  as  to 
expose  the  roots  of  grasses  or  even  of  forest  trees  to  be 
parched  by  the  sun,  destroy  immense  numbers  of  plants. 
So  too  with  wood-boring  and  leaf-eating  insects,  and  snails, 
which  consume  great  quantities  of  leaves. 

413.  Some  Modes  of  Protection  from  Animals.  —  Many 
of  the  characteristics  of  plants  may  be  wholly  or  partly 
due  to  adaptations  for  protective  purposes,  while  in  par- 
ticular cases  we  cannot  be  sure  of  the  fact.     Perching  on 
lofty  rocks  or  on  branches  of  trees,  burying  the  perennial 
part  (bulb,  rootstock,  etc.)  underground,  growing  in  dense 
masses,  like  a  canebrake  or  a  thicket  of  blackberry  bushes ; 
all  such  habits  of  plants  may  be  partly  or  altogether  val- 
uable to  the  plant  as  means  of  avoiding  the  attacks  of 
animals,  but  this  cannot  be  proved.     On  the  other  hand, 

345 


346  FOUNDATIONS   OF  BOTANY 

there  are  plenty  of  instances  of  structures,  habits,  or  accu- 
mulations of  stored  material  in  their  tissue  which  plants 
seem  to  have  acquired  mainly  or  entirely  as  means  of 
defense.  Some  of  the  most  important  are : 

(1)  The  habit  of  keeping  a  bodyguard  of  ants. 

(2)  Mimicking  the  appearance  of  dangerous  or  uneatable  plants,  or 

imitating  pebbles  or  earth,  so  that  they  may  be  overlooked. 

(3)  Forming   tough,  corky,  woody,    limy   or  flinty   and  therefore 

nearly  uneatable  tissue. 

(4)  Arming  exposed  parts  with  cutting  edges,  sharp  or  stinging 

hairs,  prickles,  or  thorns. 

(5)  Accumulating  unpleasant  or  poisonous  substances  in  exposed 

parts. 

414,  Ant-Plants.  —  Some  ants  live  on  vegetable  food, 
but  most  of  them  eat  only  animal  food,  and  these  latter 
are  extremely  voracious.  It  has  been  estimated  by  a 
careful  scientist,  an  authority  on  this  subject,  that  the 
ants  of  a  single  nest  sometimes  destroy  as  many  as  one 
hundred  thousand  insects  in  a  day.  The  Chinese  orange- 
growers  in  the  Province  of  Canton  have  found  how  useful 
ants  may  be  as  destroyers  of  other  insects,  and  so  they 
place  ant  nests  in  the  orange  trees  and  extend  bamboos 
across  from  one  tree  to  another,  to  serve  as  bridges  for  the 
ants  to  travel  on. 

Certain  tropical  trees,  in  order  to  insure  protection  by 
ants,  offer  them  especial  inducements  to  establish  colonies 
on  their  trunks  and  branches.  The  attractions  which  are 
offered  to  ants  by  various  kinds  of  trees  differ  greatly. 
One  of  the  most  interesting  adaptations  is  that  of  an 
acacia1  (Fig.  242),  which  furnishes  little  growths  at  the 
ends  of  the  leaflets  which  serve  as  ant  food.  These  little 

1  A.  sphaerocephala. 


HOW  PLANTS   PROTECT   THEMSELVES 


347 


growths  are  known  from  their  discoverer  as  Belt's  bodies. 
The  ants  bore  holes  into  the  large  hollow  stipular  thorns 
shown  in  the  figure,  live  in  these  thorns,  feed  on  the 
Belt's  bodies,  and  protect  the  acacia  from  insect  and  other 
enemies.  A  nectary  on  the  leaf  furnishes  additional  food 
to  the  ant  inhabitants  of  the  tree.  A  great  multitude  of 
plants,  some  of  them  herbs,  offer  more  or  less  important 


leaflet 


FIG.  242.  —  An  Ant-Plant  (Acacia). 
t,  thorns  ;  h,  hole  in  thorn  ;  n,  nectary  ;  6,  Belt's  body  on  tip  of  leaflet. 

inducements  to  attract  ant  visitors  ;  the  species  which  are 
known  to  do  this  number  over  three  thousand. 

415,  Plants  which  mimic  Plants  or  Other  Objects.  - 
Instances  of  mimicry  of  protected  plants  by  unprotected 
species  are  not  very  common.  One  of  the  best-known 
cases  is  that  of  the  dead-nettle,  which  is  so  called  because 
it  looks  like  the  stinging  nettle,  though  it  is  perfectly 
harmless.  Some  South  African  plants  (Kleinias)  appear 
to  mimic  pebbles.  Certain  Mesembryanthemums  of  the 


348 


FOUNDATIONS   OF  BOTANY 


same  region  can  hardly  be  distinguished  from  the  earth  in 
which  they  grow. 

416.  Plants  of  Uneatable  Texture.  —  Whenever  tender 
and  juicy  herbage  is  to  be  had,  plants  of  bard  and  stringy 
texture  are  left  untouched.  The  flinty-stemmed  scouring- 
rushes  (Equisetum,  Sect.  361)  and  the  dry,  tough  rushes 
are  familiar  examples  of  uneatable  plants  of  damp  soil. 
In  pastures  there  grow  such  peren- 
nials as  the  bracken  fern  and  the 
hardback  of  New  England  and  the 
iron  weed  and  vervains  of  the  Cen- 
tral States,  which  are  so  harsh  and 
woody  that  the  hungriest  browsing 


FIG.  243.  —  Spiny  Leaves  of  Barberry. 

animal  is  rarely,  if  ever,  seen  to  molest  them.  Still  other 
plants,  like  the  knotgrass  and  cinquefoil  of  our  dooryards, 
are  doubly  safe,  from  their  growing  so  close  to  the  ground 
as  to  be  hard  to  graze  and  from  their  woody  and  unpala- 
table nature.  The  date-palm  (which  can  easily  be  raised 
from  the  seed  in  the  schoolroom  or  the  laboratory)  is  an 
excellent  instance  of  the  same  uneatable  quality,  found 
in  a  tropical  or  sub-tropical  plant, 


HOW  PLANTS  PROTECT  THEMSELVES 


349 


417.  Plants  with  Weapons  for  Defense.1  —  Multitudes 
of  plants,  which  might  otherwise  have  been  subject  to  the 
attacks  of  grazing  or  browsing  animals,  have  acquired 
what  have  with  reason  been  called  weapons.  Shrubs  and 
trees  not  infrequently  produce  sharp-pointed  branches, 
familiar  in  our  own  crab-apple,  wild  plum,  thorn  trees, 
and  above  all  in  the  honey  locust  (Fig.  34),  whose  formida- 
ble thorns  often  branch  in 
a  very  complicated  man- 
ner. 

Thorns,  which  are 
really  modified  leaves,  are 
very  perfectly  exempli- 
fied in  the  barberry  (Fig. 


243).     It  is  much 


V 


FIG.  244.  —  Leaf  of  a  Night- 
shade (Solatium  atropur- 
pureum). 


moner  to  find  the  leaf 
extending  its  midrib  or 
its  veins  out  into  spiny 
points,  as  the  thistle  does,  or  bearing  spines  or  prickles  on 
its  midrib,  as  is  the  case  with  the  nightshade  shown  in  Fig. 
244,  and  with  so  many  roses.  Prickles,  which  are  merely 
hard,  sharp-pointed  projections  from  the  epidermis,  are  of 
too  common  occurrence  to  need  illustration. 

Stipules  are  not  infrequently  found  occurring  as  thorns, 
and  in  our  common  locust  (Fig.  246)  the  bud,  or  the  very 
young  shoot  which  proceeds  from  it,  is  admirably  pro- 
tected by  the  jutting  thorn  on  either  side. 

418.  Pointed,  Barbed,  and  Stinging  Hairs. -- Needle- 
pointed  hairs  are  an  efficient  defensive  weapon  of  many 
plants.  Sometimes  these  hairs  are  roughened,  like  those 

i  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  I,  p.  43Q. 


350 


FOUNDATIONS   OF  BOTANY 


of  the  bugloss  (Fig.  247,  b) ;  sometimes  they  are  decidedly 
barbed.  If  the  barbs  are  well  developed  they  may  cause 
the  hairs  to. travel  far  into  the  flesh  of  animals  and  cause 
intense  pain.  In.  the  nettle  -  (Fig.  247,  a)  the  hairs  are 
efficient  stings,  with  a  brittle  tip,  which  on  breaking  off 


FlG.  246.  —  Thorn 
Stipules  of  Locust. 


FIG.  245.  —  Euphorbia  splendens. 
The  spines  are  dead  and  dry 

stipules. 

exposes  a  sharp,  jagged 
tube    full    of    irritating 

fluid.     These    tubular    hairs, 

with  their  poisonous  contents, 

will  be  found  sticking  in  the 

skin  of  the  hand  or  the  face 
after  incautious  contact  with  nettles,  and  the  violent  itching 
which  follows  is  only  too  familiar  to  most  people. 

419,  Cutting  Leaves.  —  Some  grasses  and  sedges  are 
generally  avoided  by  cattle  because  of  the  sharp-cutting 
edges  of  their  leaves,  which  will  readily  slit  the  skin  of 
one's  hand  if  they  are  drawn  rapidly  through  the  fingers. 
Under  the  microscope  the  margins  of  such  leaves  are  seen 
to  be  regularly  and  thickly  set  with  sharp  teeth  like  those 
of  a  saw  (Fig.  247,  <?,  d). 


HOW  PLANTS  PROTECT  THEMSELVES 


351 


420.  Weapons  of  Desert  Plants.  —  In  temperate  regions, 
where  vegetation  is  usually  abundant,  such  moderate 
means  of  protection  as  have  just  been  described  are  gener- 
ally sufficient  to  insure  the  safety  of  the  plants  which  have 
developed  them.  But  in  desert  or  semi-desert  regions  the 


FIG.  247.  —  Stinging  Hairs  and  Cutting  Leaves.    (All  much  magnif  od.) 

a,  stinging  hairs  on  leaf  of  nettle  ;  ft,  bristle  of  the  bugloss  ;  c,  barbed  margin 

of  a  leaf  of  sedge  ;  d,  barbed  margin  of  a  leaf  of  grass. 

extreme  scarcity  of  plant  life  exposes  the  few  plants  that 
occur  there  to  the  attacks  of  all  the  herbivorous  animals 
that  may  encounter  them.  Accordingly,  great  numbers  of 
desert  plants  are  characterized  by  nauseating  or  poisonous 
qualities  or  by  the  presence  of  astonishingly  developed 
thorns,  while  some  combine  both  of  these  means  of  defense. 


352  FOUNDATIONS   OF  BOTANY 

421,  Offensive  or  Poisonous  Plants.  —  A  disgusting  smell 
is  one  of  the  common  safeguards  which  keep  plants  from 
being  eaten.  The  dog  fennel  (Fig.  227),  the  hound's-tongue 
(Cynoglossum),  the  Martynia,  and  the  tomato-plant  are 
common  examples  of  rank-smelling  plants  which  are  offen- 
sive to  most  grazing  animals  and  so  are  let  alone  by  them. 
Oftentimes,  as  in  the  case  of  the  jimson  weed  (Datura), 
the  tobacco-plant,  and  the  poison  hemlock  (Conium),  the 
smell  serves  as  a  warning  of  the  poisonous  nature  of  the 
plant. 

A  bitter,  nauseating,  or  biting  taste  protects  many  plants 
from  destruction  by  animals.  Buckeye,  horse-chestnut, 
and  maple  twigs  and  leaves  are  so  bitter  that  browsing 
animals  and  most  insects  let  them  alone.  Tansy,  ragweed, 
boneset,  southernwood,  and  wormwood  are  safe  for  the 
same  reason.  The  nauseous  taste  of  many  kinds  of  leaves 
and  stems,  such  as  those  of  the  potato,  and  the  fiery  taste 
of  pepper-corns,  red  peppers,  mustard,  and  horse-radish, 
make  these  substances  uneatable  for  most  animals.  Prob- 
ably both  the  smell  and  the  taste  of  onions  serve  to  insure 
the  safety  of  the  bulbs  from  the  attacks  of  most  grubs, 
and  the  hard  corm  of  the  jack-in-the-pulpit  (Ariscema) 
(Frontispiece)  is  carefully  let  alone  on  account  of  the 
blistering  nature  of  its  contents. 

Poisonous  plants  are  usually  shunned  by  grown-up 
animals,  though  the  young  ones  will  sometimes  eat  such 
plants  and  may  be  killed  by  them.  Almost  any  part  of  a 
poisonous  species  may  contain  the  poison  characteristic  of 
the  plant,  but,  for  obvious  reasons,  such  substances  are 
especially  apt  to  be  stored  in  the  parts  of  the  plant  where 
its  supply  of  reserve  food  is  kept. 


CHAPTER   XXVIII 
ECOLOGY  OF  FLOWERS 

422.  Topics  of  the  Chapter.  —  The  ecology  of  flowers  is 
concerned  mainly  with  the  means  by  which  the  transfer- 
ence of  pollen  or  pollination  is  effected,  and  with  the  ways 
in  which  pollen   is    kept   away  from  undesirable    insect 
visitors  and  from  rain. 

423.  Cross-Pollination    and    Self -Pollination.  —  It    was 
long  supposed  by  botanists  that  the  pollen  of  any  perfect 
flower  needed  only  to  be  placed  on  the  stigma  of  the  same 
flower   to  insure  satisfactory  fertilization.     But  in   1857 
and  1858  the  great  English  naturalist,  Charles  Darwin, 
stated  that  certain  kinds  of  flowers  were  entirely  dependent 
for  fertilization  on  the  transference  of  pollen  from  one 
plant  to  another,  and  he  and  other  botanists  soon  extended 
the  list  of  such  flowers  until  it  came  to  include  most  of 
the  showy,  sweet-scented,  or  otherwise  conspicuous  kinds. 
It   was   also   shown   that  probably   nearly  all   attractive 
flowers,  even  if  they  can  produce  some  seed  when  self- 
pollinated,  do  far  better  when  pollinated  from  the  flowers 
of  another  plant  of  the  same  kind.1     This  important  fact 
was  established  by  a  long  series  of  experiments  on  the 
number  and  vitality  of  seeds  produced  by  a  flower  when 
treated  with  its  own  pollen,  or  self-pollinated,  and  when 

1  See  Darwin's  Cross  and  Self -Fertilization  in  the    Vegetable  Kingdom 
(especially  Chapters  I  and  II). 

353 


354  FOUNDATIONS   OF  BOTANY 

treated  with  pollen  from  another  flower  of  the  same  kind, 
or  cross-pollinated.1 

424,  Wind-Pollinated  Flowers.2  —  It  has  already  been 
mentioned  that  some  pollen  is  dry  and  powdery,  and 
other  kinds  are  more  or  less  sticky.  Pollen  of  the  dusty 
sort  is  light,  and  therefore  adapted  to  be  blown  about 
by  the  wind.  Any  one  who  has  been  much  in  corn- 
fields after  the  corn  has  "  tasseled  "  has  noticed  the  pale 
yellow  dusty  pollen  which  flies  about  when  a  cornstalk  is 
jostled,  and  which  collects  in  considerable  quantities  on 
the  blades  of  the  leaves.  Corn  is 
monoecious,  but  fertilization  is  best 
accomplished  by  pollen  blown  from 
the  "tassel"  (stamens)  of  one  plant 

FIG.  248.-Pistil  of  a  Grass,      b    •  j   d  t      th      u    ^  „    ,    •   ^  , 

provided  with  a  Feathery 

stigma,  adapted  for  wind-    of    another    plant.       This    is    well 
shown  by  the  fact,  familiar  to  every 

observing  farmer's  boy,  that  solitary  cornstalks,  such  as 
often  grow  very  luxuriantly  in  an  unused  barnyard  or 
similar  locality,  bear  very  imperfect  ears  or  none  at 
all.  The  common  ragweed,  another  monoecious  plant, 
is  remarkable  for  the  great  quantities  of  pollen  which 
shake  off  it  on  to  the  shoes  or  clothes  of  the  passer-by, 
and  it  is  wind-pollinated.  So,  too,  are  the  monoecious 
pines,  and  these  produce  so  much  pollen  that  it  has  been 
mistaken  for  showers  of  sulphur,  falling  often  at  long  dis- 
tances from  the  woods  where  it  was  produced.  The  pistil 
of  wind-pollinated  flowers  is  often  feathery  and  thus 
adapted  to  catch  flying  pollen-grains  (Fig.  248).  Other 

1  On  dispersion  of  pollen  see  Kerner  and  Oliver,  Vol.  II,  pp.  129-287. 

2  See  Miss  NewelFs  Botany  Reader,  Part  II,  Chapter  VII. 


ECOLOGY   OF  FLOWERS  355 

characteristics  of  such  flowers  are  the  inconspicuous  char- 
acter of  their  perianth,  which  is  usually  green  or  greenish, 
the  absence  of  odor  and  of  nectar,  the  regularity  of  the 
corolla,  and  the  appearance  of  the  flowers  before  the  leaves 
or  their  occurrence  on  stalks  raised  above  the  leaves. 

Pollen  is,  in  the  case  of  a  few  aquatic  plants,  carried 
from  flower  to  flower  by  the  water  on  which  it  floats. 

425.  Insect-Pollinated  Flowers.  —  Most    plants    which 
require  cross-pollination  depend  upon  insects    as  pollen- 
carriers,1  and  it  may  be  stated  as  a  general  fact  that  the 
showy  colors  and  markings  of  flowers  and  their  odors  all 
serve  as  so  many  advertisements  of  the  nectar  (commonly 
but  wrongly  called  honey)   or  of  the   nourishing  pollen 
which  the  flower  has  to  offer  to  insect  visitors. 

Many  insects  depend  mainly  or  wholly  upon  the  nectar 
and  the  pollen  of  flowers  for  their  food.  Such  insects 
usually  visit  during  any  given  trip  only  one  kind  of  flower, 
and  therefore  carry  but  one  kind  of  pollen.  Going  straight 
from  one  flower  to  another  with  this,  they  evidently  waste 
far  less  pollen  than  the  wind  or  water  must  waste.  It  is 
therefore  clearly  advantageous  to  flowers  to  develop  such 
adaptations  as  fit  them  to  attract  insect  visitors,  and  to 
give  pollen  to  the  latter  and  receive  it  from  them. 

426.  Pollen-Carrying  Apparatus  of  Insects.2  —  Ants  and 
some  beetles  which  visit  flowers  have  smooth  bodies,  to 
which  little  pollen  adheres,  so  that  their  visits  are  often  of 
slight  value  to  the  flower,  but  many  beetles,  all  butterflies 
and  moths,  and  most  bees  have   bodies  roughened  with 
scales  or  hairs  which  hold  a  good  deal  of  pollen  entangled. 

1  A  few  are  pollinated  by  snails ;  many  more  by  humming-birds  and  other 
birds.  2  See  Muller's  Fertilization  of  Flowers,  Part  II. 


356 


FOUNDATIONS   OF  BOTANY 


In  the  common  honey-bee  (and  in  many  other  kinds)  the 
greater  part  of  the  insect  is  hairy,  and  there  are  special 
collecting  baskets,  formed  by  bristle-like  hairs,  on  the  hind 

legs  (Fig.  249).  It  is  easy 
to  see  the  load  of  pollen 
accumulated  in  these  bas- 
kets after  such  a  bee  has 
visited  several  flowers.  Of 
course  the  pollen  which  the 
bee  packs  in  the  baskets  and 
carries  off  to  the  hive,  to  be 
stored  for  food,  is  of  no  use 
in  pollination.  In  fact  such 
pollen  is  in  one  sense  entirely 
wasted.  But  since  such 
bees  as  have  these  collects 
ing  baskets  are  the  most 
industrious  visitors  to  flowers,  they  accomplish  an  immense 
share  of  the  work  of  pollination  by  means  of  the  pollen 
grains  which  stick  to  their  hairy  coats  and  are  then  trans- 
ferred to  other  flowers  of  the  same  kind  next  visited  by 
the  bee. 

427.  Nectar  and  Nectaries.  —  Nectar  is  a  sweet  liquid 
which  flowers  secrete  for  the  purpose  of  attracting  insects. 
After  partial  digestion  in  the  crop  of  the  bee,  nectar 
becomes  honey.  Those  flowers  which  secrete  nectar  do 
so  by  means  of  nectar  glands,  small  organs  whose  structure 
is  something  like  that  of  the  stigma,  situated  often  near 
the  base  of  the  flower,  as  shown  in  Fig.  250.  Sometimes 
the  nectar  clings  in  droplets  to  the  surface  of  the  nectar 
glands  ;  sometimes  it  is  stored  in  little  cavities  or  pouches 


FIG.  249. 

A,  right  hind  leg  of  a  honey-bee  (seen  from 
behind  and  within);  B,  the  tibia,  ti, 
seen  from  the  outside,  showing  the  col- 
lecting basket  formed  of  stiff  hairs. 


ECOLOGY   OF   FLOWERS 


35T 


called  nectaries.     The  pouches  at  the  bases  of  columbine 
petals  are  among  the  most  familiar  of  nectaries. 

428.  Odors  of  Flowers.  —  The  acuteness  of  the  sense  of 
smell  among  insects  is  a  familiar  fact.     Flies  buzz  about 
the  wire  netting  which  covers  a  piece  of  fresh  meat  or  a 
dish  of   syrup,  and  bees,  wasps,  and  hornets  will  fairly 
besiege  the  window  screens  of  a  kitchen  where  preserving 
is  going  on.     Many  plants  find  it  possible  to  attract  as 
many  insect  visitors  as  they  need  without  giving  off  any 
scent,  but  small  flowers,  like  the  mignonette,  and  night- 
blooming  ones,   like  the  white   tobacco  and  the  evening 
primrose,  are  sweet-scented  to  attract  night-flying  moths. 
It  is  interesting  to  observe  that  the  majority  of  the  flowers 
which  bloom  at  night  are  white,  and  that  they  are  much 
more   generally  sweet-scented  than  flowers  which  bloom 
during  the   day.     A  few  flowers  are 
carrion-scented  (and  purplish  or  brown- 
ish colored)  and  attract  flies. 

429,  Colors  of    Flowers.  —  Flowers 
which  are  of  any  other  color  than  green 
probably  in  most  cases   display  their 
colors  to  attract  insects,  or  occasionally 
birds.  The  principal  color  of  the  flower 
is  most  frequently  due  to  showy  petals; 
sometimes,  as  in  the  marsh  marigold,  it 
belongs  to  the  sepals;  and  not  infre- 
quently, as  income  cornels  and  Eu- 
phorbias (Fig.  245),  the  involucre  is  more  brilliant  and 
conspicuous  than  any  part  of  the  flower  strictly  so  called. 

Different    kinds    of    insects    appear   to   be    especially 
attracted  by  different  colors.      In    general,  dull   yellow, 


FIG.  250.  —  Stamens  and 
Pistil  of  the  Grape 
(magnified),  with  a 
Nectar  Glaiid,  g,  be- 
tween Each  Pair  of 
Stamens. 


358  FOUNDATIONS   OF  BOTANY 

brownish,  or  dark  purple  flowers,  especially  if  small,  seem 
to  depend  largely  on  the  visits  of  flies.  Red,  violet,  and 
blue  are  the  colors  by  which  bees  and  butterflies  are  most 
readily  enticed.  The  power  of  bees  to  distinguish  colors 
has  been  shown  by  a  most  interesting  set  of  experiments 
in  which  daubs  of  honey  were  put  on  slips  of  glass  laid  on 
separate  pieces  of  paper,  each  of  a  different  color,  and 
exposed  where  bees  would  find  them.1 

It  is  certain,  however,  that  colors  are  less  important 
means  of  attraction  than  odors  from  the  fact  that  insects 
are  extremely  near-sighted.  Butterflies  and  moths  cannot 
see  distinctly  at  a  distance  of  more  than  about  five  feet, 
bees  and  wasps  at  more  than  two  feet,  and  flies  at  more 
than  two  and  a  fourth  feet.  Probably  no  insects  can  make 
out  objects  clearly  more  than  six  feet  away.2  Yet  it  is 
quite  possible  that  their  attention  is  attracted  by  colors  at 
distances  greater  than  those  mentioned. 

430,  Nectar  Guides.  —  In  a  large  number  of  cases  the 
petals  of  flowers  show  decided  stripes  or  rows  of  spots,  of 
a  color  different  from  that  of  most  of  the  petal.     These 
commonly  lead  toward  the  nectaries,  and  it  is  possible  that 
such  markings  point  out  to  insect  visitors  the  way  to  the 
nectaries.     Following   this    course,   the    insect   not   only 
secures  the  nectar  which  he  seeks,  but  probably  leaves 
pollen  on  the  stigma  and  becomes  dusted  with  new  pollen, 
which  he  carries  to  another  flower. 

431,  Facilities  for  Insect  Visits.  —  Regular  polypetalous 
flowers  have  no  special  adaptations  to  make  them  singly 

1  See  Lubbock's  Flowers,  Fruits,  and  Leaves,  Chapter  I.     On  the  general 
subject  of  colors  and  odors  in  relation  to  insects,  see  Miiller's  Fertilization  of 
Flowers,  Part  IV. 

2  See  Packard's  Text-Book  of  Entomology,  p.  260. 


ECOLOGY   OF   ELOWERS 


359 


accessible  to  insects,  but  they  lie  open  to  all  comers. 
They  do,  however,  make  themselves  much  more  attractive 
and  afford  especial  inducements  in  the  matter  of  saving 
time  to  flower-frequenting  insects  by  being  grouped.  This 
purpose  is  undoubtedly  served  by  dense  flower-clusters, 
especially  by  heads  like  those  of  the  clovers  and  by  the 
peculiar  form  of  head  found  in  so-called  composite  flowers, 
like  the  sunflower,  the  bachelor's  button,  and  the  yarrow 
(Fig.  183).  In  many  such  clusters  the  flowers  are  special- 
ized, some  carrying  a  showy  strap- 
shaped  corolla,  to  serve  as  an 
advertisement  of  the  nectar  and 
pollen  contained  in  the  inconspicu- 
ous tubular  flowers  (see  Plate  XI). 
Irregular  flowers  probably  always 
are  more  or  less  adapted  to  par- 
ticular insect  (or  other)  visitors. 
The  adaptations  are  extremely  nu- 
merous ;  —  here  only  a  very  few  of 
the  simpler  ones  will  be  pointed 
out.  Where  there  is  a  drooping 
lower  petal  (or,  in  the  case  of  a  gamopetalous  corolla,  a 
lower  lip),  this  serves  as  a  perch  upon  which  flying  insects 
may  alight  and  stand  while  they  explore  the  flower,  as  the 
beetle  is  doing  in  Fig.  251.  In  Fig.  252  one  bumblebee 
stands  with  his  legs  partially  encircling  the  lower  lip  of 
the  dead-nettle  flower,  while  another  perches  on  the  sort 
of  grating  made  by  the  stamens  of  the  horse-chestnut 
flower.  The  honey-bee  entering  the  violet  clings  to  the 
beautifully  bearded  portion  of  the  two  lateral  petals,  while 
it  sucks  the  nectar  from  the  spur  beneath. 


FlG.  251.— A  Beetle  on  the 

Flower  of  the  Twayblade. 

(Enlarged  three  times.) 


360 


FOUNDATIONS   OF  BOTANY 


432.  Protection  of  Pollen  from  Unwelcome  Visitors.  —  It 
is  usually  desirable  for  the  flower  to  prevent  the  entrance 
of  small  creeping  insects,  such  as  ants,  which  carry  little 
pollen  and  eat  a  relatively  large  amount  of  it.  The  means 
adopted  to  secure  this  result  are  many  and  curious.  In 


FIG.  252.  —  Bees  visiting  Flowers. 

At  the  left  a  bumblebee  on  the  flower  of  the  dead  nettle ;  below  a  similar 
bee  in  the  flower  of  the  horse-chestnut ;  above  a  honey-bee  in  the  flower 
of  a  violet. 

some  plants,  as  the  common  catchfly,  there  is  a  sticky 
ring  about  the  peduncle,  some  distance  below  the  flowers, 
and  this  forms  an  effectual  barrier  against  ants  and  like 
insects.  Very  frequently  the  calyx  tube  is  covered  with 
hairs,  which  are  sometimes  sticky.  How  these  thickets 
of  hairs  may  appear  to  a  very  small  insect  can  perhaps 
be  more  easily  realized  by  looking  at  the  considerably 


ECOLOGY   OF  FLOWERS 


361 


magnified  view  of   the   hairs  from  the   outer  surface  of 
mullein  petals,  shown  in  Fig.  253.1 

Sometimes  the  recurved  petals  or  divisions  of  the  corolla 
stand  in  the  way  of  creeping  insects.     In  other  cases  the 


FIG.  253.  —  Branching  Hairs  from  the  Outside  of  the  Corolla  of  the  Common 
Mullein.    (Magnified.)    dr,  a  gland. 


FIG.  254.  — A  Sphinx  Moth,  with  a  Long  Sucking-Tube. 

throat  of  the  corolla  is  much  narrowed  or  closed  by  hairs, 
or  by  appendages.     Those  flowers  which  have  one  or  more 

1  On  protection  of  pollen,  see  Kerner  and  Oliver^  Vol.  II,  pp.  95- 109. 


362  FOUNDATIONS   OF   BOTANY 

sepals  or  petals  prolonged  into  spurs,  like  the  nasturtium 
and  the  columbine,  are  inaccessible  to  most  insects  except 
those  which  have  a  tongue  or  a  sucking-tube  long  enough 
to  reach  to  the  nectary  at  the  bottom  of  the  spur.  The 
large  sphinx  moth,  shown  in  Fig.  254,  which  is  a  common 
visitor  to  the  flowers  of  the  evening  primrose,  is  an 
example  of  an  insect  especially  adapted  to  reach  deep  into 
long  tubular  flowers. 

A  little  search  among  flowers,  such  as  those  of  the 
columbine  or  the  foxglove,  will  usually  disclose  many 
which  have  had  the  corolla  bitten  through  by  bees,  which 
are  unable  to  get  at  the  nectar  by  fair  means  or  unwilling 
to  take  the  trouble  to  do  so ;  and  they  therefore  steal  it. 

433,  Bird-Pollinated  Flowers.  —  Some  flowers  with  very 
long  tubular  corollas  depend  entirely  upon  birds  to  carry 
their  pollen  for  them.     Among  garden  flowers  the  gladi- 
olus, the  scarlet  salvia,  and  the  trumpet  honeysuckle  are 
largely  dependent  upon  humming-birds  for  their  pollination. 
The  wild  balsam  or  jewel-weed  and  the  trumpet-creeper 
(Plate  X)  are  also  favorite  flowers  of  the  humming-bird. 

434,  Prevention  of  Self -Fertilization.  —  Dioecious  flowers 
are  of  course  quite  incapable  of  self-pollination.    Pistillate 
monoecious  flowers  may  be  pollinated  by  staminate  ones 
on  the  same  plant,  but  this  does  not  secure  as  good  seed 
as  is  secured  by  having  pollen  brought  to  the  pistil  from 
a  different  plant  of  the  same  kind. 

In  perfect  flowers  self-pollination  would  commonly  occur 
unless  it  were  prevented  by  the  action  of  the  essential 
organs  or  by  something  in  the  structure  of  the  flower.  In 
reality  many  flowers  which  at  first  sight  would  appear  to 
be  designed  to  secure  self-pollination  are  almost  or  quite 


H 


ECOLOGY   OF  FLOWERS 


363 


incapable  of  it.  Frequently  the  pollen  from  another  plant 
of  the  same  species  prevails  over  that  which  the  flower 
may  shed  on  its  own  pistil,  so  that  when  both  kinds  are 
placed  on  the  stigma  at  the  same  time  it  is  the  foreign 
pollen  which  causes  fertilization.  But  apart  from  this 
fact  there  are  several  means  of  insuring  the  presence  of 
foreign  pollen,  and  only  that,  upon  the  stigma,  just  when 
it  is  mature  enough  to 
receive  pollen  tubes. 

435 .  Stamens  and  Pistils 
maturing  at  Different 
Times.  —  If  the  stamens 
mature  at  a  different  time 
from  the  pistils,  self-polli- 
nation is  as  effectually  pre- 
vented as  though  the  plant 
were  dioecious.  This  un- 
equal maturing  or  dichog- 
amy occurs  in  many  kinds 
of  flowers.  In  some,  the 

figWOrt  and  the  COmniOll  jn  ^4  (earlier  stage)  the  stamens  are  mature, 
plantain  for  example,  the  while  the  pistil  is  stillundeyeloped  and  bent 

to  one  side.    In  B  (later  stage)  the  stamens 

pistil    develops    before    the       have  withered  and  the  stigmas  have  sepa- 
rated, ready  for  the  reception  of  pollen. 

stamens,   but   usually  the 

reverse  is  the  case.  The  Clerodendron,1  a  tropical  African 
flower  ^Fig.  255),  illustrates  in  a  most  striking  way  the 
development  of  stamens  before  the  pistil.  The  insect  visitor, 
on  its  way  to  the  nectary,  can  hardly  fail  to  brush  against 
the  protruding  stamens  of  the  flower  in  its  earlier  stage 
(at  A),  but  it  cannot  deposit  any  pollen  on  the  stigmas, 

1  C.  Thompsonise. 


FIG.  255.  —  Flower  of  Clerodendron  in  Two 


364 


FOUNDATIONS   OF   BOTANY 


which  are  unripe,  shut  together,  and  tucked  aside  out  of 
reach.  On  flying  to  a  flower  in  the  later  stage  the  pollen 
just  acquired  will  be  lodged  on  the  prominent  stigmas  and 
thus  produce  the  desired  cross-pollination. 


-—stig 


i  ii  in  iv 

FIG.  256.  —  Provisions  for  Cross-Pollination  in  the  High  Mallow. 

I,  essential  organs  as  found  in  the  bud  ;  II,  same  in  the  staminate  stage,  the 
anthers  discharging  pollen,  pistils  immature  ;  III,  intermediate  stage, 
slig,  the  united  stigmas  ;  IV,  pistillate  stage,  the  stigmas  separated, 
stamens  withered, 

Closely  related  flowers  often  differ  in  their  plan  of 
pollination.  The  high  mallow,  a  plant  cultivated  for  its 
purplish  flowers,  which  has  run  wild  to  some  extent,  is 
admirably  adapted  to  secure  cross-pollination,  since  when 
its  stamens  are  shedding  pollen,  as  in 
Fig.  256,  II,  the  pistils  are  incapable  of 
receiving  it,  while  when  the  pistils  are 
mature,  as  at  IV,  the  stamens  are  quite 
withered.  In  the  common  low  mallow 
of  our  dooryards  and  waysides'  insect 
pollination  may  occur,  but  if  it  does  not 

FiG.257.-Stamens     *  / 

and  Pistils  of  Round-    the  curling  stigmas  finally  come  in  con- 


tact   ™th   the   Projecting    stamens    and 
among  the  stamens    receive  pollen  from  them,  as  is  indicated 

to  admit  Of  Self-pol-       .         -.-,.          nrrr 

lination.  m    tig.   257. 


ECOLOGY   OF  FLOWERS 


365 


436.    Movements  of  Floral  Organs  to  aid  in  Pollination. 

—  Besides  the  slow  movements  which  the  stamens  and 
pistil  make  in  such  cases  as  those  of  the  Clerodendron  and 
the  mallow,  already  described,  the  parts  of  the  flower 
often  admit  of  considerable  and  rather  quick  movements 
to  assist  the  insect  visitor  to  become  dusted  or  smeared 
with  pollen. 

In  some  flowers  whose  stamens  perform  rapid  move- 
ments when  an  insect  enters,  it  is  easy  to  see  how  directly 


FIG.  258.  —  Two  Flowers  of  Common  Sage,  one  of  them  visited  by  a  Bee. 

useful  the  motion  of  the  stamens  is  jn  securing  cross- 
pollination.  The  stamens  of  the  laurel,  Kalmia,  throw 
little  masses  of  pollen,  with  a  quick  jerk,  against  the 
body  of  the  visiting  insect.  Barberry  stamens  spring  up 
against  the  visitor  and  dust  him  with  pollen.  The  common 
garden  sage  matures  its  anthers  earlier  than  its  stigmas. 
In  Fig.  258,  J.,  the  young  flower  is  seen,  visited  by  a  bee, 
and  one  anther  is  shown  pressed  closely  against  the  side 
of  the  bee's  abdomen.  The  stigma,  st,  is  hidden  within 
the  upper  lip  of  the  corolla.  In  B,  an  older  flower,  the 


366 


FOUNDATIONS   OF  BOTANY 


anthers  have  withered  and  the  stigma  is  now  lowered  so 
as  to  brush  against  the  body  of  any  bee  which  may  enter. 

A  little  study  of  Fig.  259 
will  make  clear  the  way 
in  which  the  anthers  are 
hinged,  so  that  a  bee  strik- 


FIG.  259.  —  Flower  and  Stamens  of  Common  Sage. 

A,  p,  stigma  ;  a,  anthers  ;  B,  the  two  stamens  in  ordinary  position  ;  /,  filaments  ; 
m,  connective  (joining  anther-cells)  ;  a',  anther-cells  ;  C,  the  anthers  and 
connectives  bent  into  a  horizontal  position  by  an  insect  pushing  against  a. 

ing  the  empty  or  barren  anther-lobes,  a,  knocks  the  pollen- 
bearing  lobes,  a',  into  a  horizontal  position,  so  that  they 
will  lie  closely  pressed  against  either  side  of  its  abdomen. 

437.  Flowers  with  Sta- 
mens and  Pistils  Each  of  Two 
Lengths.  —  The  flowers  of 
bluets,  partridge-berry,  the 
primroses,  and  a  few  other 
common  plants  secure  cross- 
pollination  by  having  essen- 
tial organs  of  two  forms 
(Fig.  260).  Such  flowers 
are  said  to  be  dimorphous 
(of  two  forms).  In  the 
short-styled  flowers,  II,  the 
anthers  are  borne  at  the  top 


FlG.  260.  —  Dimorphous  Flowers  of 

the  Primrose. 

1,  a  long-styled^flower  ;  II,  a  short- 


Q£ 


ECOLOGY   OF  FLOWERS  367 

stigma  stands  about  halfway  up  the  tube.  In  the  long- 
styled  flowers,  I,  the  stigma  is  at  the  top  of  the  tube  and 
the  anthers  are  borne  about  halfway  up.  An  insect  pressing 
its  head  into  the  throat  of  the  corolla  of  II  would  become 
dusted  with  pollen,  which  would  be  brushed  off  on  the 
stigma  of  a  flower  like  I.  On  leaving  a  long-styled  flower 
the  bee's  tongue  would  be  dusted  over  with  pollen,  some 
of  which  would  necessarily  be  rubbed  off  on  the  stigma  of 
the  next  short-styled  flower  that  was  visited.  Cross-polli- 
nation is  insured,  since  all  the  flowers  on  a  plant  are  of 
one  kind,  either  long-styled  or  short-styled,  and  since  the 
pollen  is  of  two  sorts,  each  kind  sterile  on  the  stigma  of 
any  flower  of  similar  form  to  that  from  which  it  came. 

Trimorphous  flowers,  with  long,  medium,  and  short 
styles,  are  found  in  a  species  of  loosestrife.1 

438.  Studies  in  Insect  Pollination.  —  The  student  cannot  gather 
more  than  a  very  imperfect  knowledge  of  the  details  of  cross-polli- 
nation in  flowers  without  actually  watching  some  of  them  as  they 
grow,  and  observing  their  insect  visitors.  If  the  latter  are  caught 
and  dropped  into  a  wide-mouthed  stoppered  bottle  containing  a  bit 
of  cotton  saturated  with  chloroform,  they  will  be  painlessly  killed, 
and  most  of  them  may  be  identified  by  any  one  who  is  familiar  with 
our  common  insects.  The  insects  may  be  observed  and  classified 
in  a  general  way  into  butterflies,  moths,  bees,  flies,  wasps,  and  beetles, 
without  being  captured  or  molested. 

Whether  these  out-of-door  studies  are  made  or  not,  several  flowers 
should  be  carefully  examined  and  described  as  regards  their  arrange- 
ments for  attracting  and  utilizing  insect  visitors  (or  birds).  The 
followingflist  includes  a  considerable  number  of  the  most  accessible 
flowers  of  spring  and  early  summer,  about  which  it  is  easy  to  get 
information  from  books. 

1  See  Miss  Newell's  Reader  in  Botany,  Part  II,  pp.  60-63. 


868 


FOUNDATIONS  OF  BOTANY 


LIST   OF   INSECT-POLLINATED   FLOWERS.1 


1.  Flax     .     .     .     . 

2.  Missouri  currant 

3.  Snowberry     .     . 

4.  Lilac    .... 

5.  Periwinkle     .     . 

6.  Mignonette    .     . 

7.  Pansy  .... 

8.  Dead  nettle    .     . 

9.  Bleeding  heart   . 

10.  Columbine     .     . 

11.  Monkshood    . 


Linum  usitatissimum Mull. 

Eibes  aureum Mull. 

Symphoricarpus  racemosus     ....  Mull. 

Syringa  persica Mull. 

Vinca  minor Mull. 

Reseda  odorata Mull. 

Viola  tricolor Mull. 

Lamium  album Lubbock. 

Dicentra  (Diclytra)  spectabilis     .     .     .  Mull. 

Aquilegia  vulgaris Mull. 

Aconitum  Napellus Mull. 


12.  Larkspur  .     .     . 

13.  Herb  Robert .     . 

14.  Pink     .... 

15.  Fireweed  .     .     . 

16.  Nasturtium    .     . 

17.  Lily-of -the- valley 

18.  Heal-all     .     .     . 

19.  Ground  ivy    .     . 

20.  Lousewort     .     . 

21.  Snapdragon  .     . 

22.  Iris 

23.  Bellflower      .     . 

24.  Horse-chestnut  . 


II 


Delphinium  elatum,  D.  consolida     . 

Geranium  robertianum 

Dianthus  (various  species)  .  .  . 
Epilobium  angustifolium  .... 
Tropceolum  majus  .  .  .  Newell, 

Convallaria  majalis 

Brunella  (Prunella)  vulgaris  .     . 
Nepeta  Glechoma     ....     Miill 
Pedicularis  canadensis .     .     .     Mull 

Antirrhinum  majus 

Iris  versicolor       

Campanula  rapunculoides  .  .  . 
^Esculus  Hippocastanum  .... 


.     Mull. 

.     Miill. 

.     Miill. 

.    Gray. 

Lubbock. 

.     Miill. 

.     Miill. 

.,  Newell. 

Newell. 

Miill. 

Newell. 

Miill. 

Newell. 


1  The  plants  in  this  list  are  arranged  somewhat  in  the  order  of  the  com- 
plexity of  their  adaptations  for  insect  pollination,  the  simplest  first.  It  would 
be  well  for  each  student  to  take  up  the  study  of  the  arrangements  for  the 
utilization  of  insect  visitors  in  several  of  the  groups  above,  numbered  with 
Roman  numerals.  The  teacher  will  find  explanations  of  the  adaptations  in 
the  works  cited  by  abbreviations  at  the  right.  Miill.  stands  for  Muller's  Fer- 
tilization of  Flowers;  Lubbock,  for  British  Wild  Flowers,  considered  in 
Relation  to  Insects;  Gray,  for  Gray's  Structural  Botany;  and  Newell,  for 
Miss  NewelPs  Outlines  of  Lessons  in  Botany,  Part  II.  Consult  also  Weed's 
Ten  New  England  Blossoms. 


ECOLOGY   OF  FLOWERS  369 


III 

25.  Yarrow     ....     Achillea  millefolium Mull. 

26.  Oxeye  daisy  .     .     .     Chrysanthemum  Leucanthemum  .     .     .     Mull. 

27.  Dandelion      .     .     .     Taraxacum  officinale     .     .     .    Mull.,  Newell. 

IV 

28.  Barberry  ....     Berberis  vulgaris Lubbock. 

29.  Mountain  laurel      .     Kalmia  latifolia Gray. 


30.  White  clover .     .     .     Trifolium  repens Mtill. 

31.  Red  clover     .     .     .     Trifolium  pratense Mull. 

32.  Locust Eobinia  Pseudacacia Gray. 

33.  Wistaria    ....     Wistaria  sinensis Gray. 

34.  Vetch Vicia  cracca Mull. 

35.  Pea ,  Pisum  sativum Mtill. 

36.  Bean Phaseolus  vulgaris Gray. 

37.  Ground-nut   .     .     .     Apios  tuberosa Gray. 

VI 

38.  Partridge-berry  .     .     Mitchella  repens Gray. 

39.  Primrose  ....     Primula  grandiflora,  P.  officinalis  .  Lubbock. 

40.  Loosestrife    .     .     .     Lythrum  Salicaria Gray. 

VII 

41.  Milkweed.     .     .     ,    Asdepias  Cornuti     ....    Mtill.,  Newell. 

VIII 

42.  Lady's-slipper    .     .     Cypripedium  acaule Newell. 

439.  Cleistogamous  Flowers.  —  In  marked  contrast  with 
such  flowers  as  those  discussed  in  the  preceding  sections, 
which  bid  for  insect  visitors  or  expose  their  pollen  to  be 
blown  about  by  the  wind,  are  certain  flowers  which  remain 
closed  even  during  the  pollination  of  the  stigma.  These 
flowers  are  called  cleistogamous  and  of  course  are  not 


370 


FOUNDATIONS   OF  BOTANY 


cross-pollinated.      Usually  they    occur    on   plants    which 
also  bear  flowers  adapted  for  cross-pollination,  and  in  this 


FIG.  261.  — A  Violet,  with  Cleistogamous  Flowers. 

The  objects  which  look  like  flower-buds  are  cleistogamous  flowers  in  various 
stages  of  development.  The  pods  are  the  fruit  of  similar  flowers.  The 
plant  is  represented  as  it  appears  in  late  July  or  August,  after  the  ordi- 
nary flowers  have  disappeared. 


ECOLOGY   OF  FLOWERS 


371 


case  the  closed  flowers  are  much  less  conspicuous  than 
the  others,  yet  they  produce  much  seed.  Every  one 
knows  the  ordinary  flowers  of  the  violet,  but  most  people 


FIG.  '2G2.  —  Protection  of  Pollen  from  Moisture. 

At  the  left  herb  Robert  and  sweet  scabious  in  sunny  weather  ;  at  the  right 
the  same  flowers  during  rain. 

do  not  know  that  violets  very  generally,  after  the  blos- 
soming season  (of  their  showy  flowers)  is  over,  produce 
many  cleistogamous  flowers,  as  shown  in  Fig.  261. 


372  FOUNDATIONS   OF  BOTANY 

440.  Protection  of  Pollen  from  Rain.  —*  Pollen  is  very 
generally  protected  from  being  soaked  and  spoiled  by  rain 
or  dew  either  by  the  natural  position  of  the  flower  prevent- 
ing rain  from  entering,  as  in  the  case  with  most  gamo- 
petalous,  nodding  flowers,  or  by  changes  in  the  position 
of  the  flower,  and  by  its  opening  in  sunny  weather  and 
closing  at  night  or  during  rain.  Sometimes  the  flower 
both  changes  its  position  and  closes,  as  is  the  case  with 
the  herb  Robert  and  the  sweet  scabious  (Fig.  262).  The 
adaptations  of  flowers  to  protect  their  pollen  from  becom- 
ing wet  can  best  be  understood  by  actually  examining  the 
same  flower  in  sunshine  and  during  rain. 


PLATE  XI.  —  Aster  and  Golden-Rod 


CHAPTER    XXIX 
HOW    PLANTS    ARE   SCATTERED   AND    PROPAGATED 

441.  Means  of  Propagation  among  Cryptogams.  —  Some 
of  the  highest  cryptogams,  as  the  ferns,  spread  freely  by 
means  of  their  creeping  rootstocks,  and  the  gardener  who 
wishes  quickly  to  get  large,  strong  ferns  often  finds  it  the 
easiest  plan  to  cut  to  pieces  and  reset  the  rootstocks  of  a 
well-established  plant.     Some  ferns  also  grow  readily  from 
bulblets  produced  on  the  fronds.      In  the  walking  fern 
the  tip  of  the  frond  roots  and  begins  a  new  plant.     Most 
flowerless  plants,  however,   are  reproduced   either   by  a 
process  of  fission,  as  in  Pleurococcus  (Sect.  278),  Diatoms 
(Sect.  271),  Bacteria  (Sect.  266),  and  many  other  groups, 
or  by  some   kind   of   spore   (Sect.   259).     The  spore   is 
usually  so  small  an  object  that  it  is  carried  with  the  great- 
est ease  by  currents  of  water  or  of  air,  as  the  case  may 
be,  so  that  it  is  no  sooner  liberated  than  it  is  swept  away, 
often  to  a  very  distant  locality,  where  it  can  grow  and  not 
be  interfered  with  by  too  many  neighbors  of  its  own  kind. 
Thus  spores  of  any  of  the  marine  algae  are  certainly  carried 
thousands  of  miles  by  ocean  currents,  and  spores  of  tree 
ferns  may  be  blown  great  distances  from  one  oceanic  island 
to  another,  or  the  spore  contents  of  a  puff-ball  might  travel 
on  the  wind  half  the  breadth  of  a  continent. 

442.  Dispersal  of  Seed-Plants  by  Roots  and  Rootstocks.— 
The  student  has  learned  (in   Chapters  IV  and  V)   that 
roots  and  underground  stems  of  many  kinds  may  serve  to 

373 


374  FOUNDATIONS   OF   BOTANY 

reproduce  the  plant.  Either  roots  or  rootstocks  may  travel 
considerable  distances  horizontally  in  the  course  of  their 
growth  and  then  shoot  up  and  produce  a  new  plant,  which 
later  becomes  independent  of  the  parent.  The  sedges  (Fig. 
43)  are  excellent  illustrations  of  this  process,  and  trees 


like  the  common 
locust  and  the 
silver-leaf  poplar 
become  great  nui- 
sances in  the  neigh- 
borhood of  lawns 

FIG.  263. —  Plant    of    a  Black 

Raspberry,  showing  One  and    gardens    by 

in  many  places.  When  growing 
wild,  such  trees  as  these  depend  largely  upon  spreading 
by  the  roots  to  keep  up  their  numbers.1 

443.  Dispersal  of  Seed-Plants  by  Branches.  —  There  is  a 
shrub  of  the  Honeysuckle  Family,2  common  in  the  northern 
woods,  which  is  quite  generally  known  as  hobble-bush,  or 
witch-hobble,  and  sometimes  as  trip-toe.  This  is  because 
the  branches  take  root  at  the  end  and  so  form  loops  which 
catch  the  foot  of  the  passer-by.  The  same  habit  of  growth 
is  found  in  the  raspberry-bush  (Fig.  263),  in  one  species  of 
strawberry-bush  (Euonymus),  and  some  other  shrubs.  Many 
herbs  like  the  strawberry-plant  and  the  cinquefoil  send 

1  See  Beal's  Seed  Dispersal,  Chapters  II  and  III. 

2  Viburnum  lantanoides. 


HOW   PLANTS   ARE   SCATTERED 


375 


out  long,  leafless  runners  which  root  at  intervals  and  so 
propagate  the  plant,  carrying  the  younger  individuals  off 
to  a  considerable  distance  from  the  parent  plant. 

Living  branches  may  drop  freely  from  the  tree  and  then 
take  root  and  grow,  after  having  been  blown  or  been  car- 
ried by  a  brook  or  river  to  a  favorable  spot,  perhaps  hun- 
dreds of  yards  away.  The  so-called  snap-willows  lose 
many  live  twigs  under  conditions  suit- 
able for  starting  new  trees. 

A  slightly  different  mode  of  dis- 
persal from  that  of 
the  raspberry  is  one 
in  which  buds  sepa- 
rate from  the  plant 
and  serve  to  propa- 
gate it.  In  the  blad- 
derwort  (Fig.  264), 

at     the     close     Of     the  FlQ-  264.  —  A  Free  Branch  and  Two  Buds  of 

Bladder  wort. 

growing   season,    the 

terminal  buds  are  released  by  the  decay  of  the  stem  and 
sink  to  the  bottom  of  the  water  in  which  the  plants  live, 
there  to  remain  dormant  until  spring.  Then  each  bud 
starts  into  life  and  gives  rise  to  a  new  individual. 

444.  Dispersal  of  Seed-Plants  by  Bulblets.  —  Almost 
every  farmer's  boy  knows  what  "  onion-sets  "  are.  These 
are  little  bulbs,  produced  at  the  top  of  a  naked  flower- 
stalk  or  scape  by  some  kinds  of  onions  which  do  not 
usually  flower  or  bear  seed.  Tiger-lilies  produce  some- 
what similar  bulblets  in  the  axils  of  the  leaves,  and  there 
is  a  large  number  of  species,  scattered  among  numerous 
families  of  plants,  all  characterized  by  the  habit  of  producing 


376 


FOUNDATIONS   OF   BOTANY 


bulblets.  When  mature  the  bulblets  fall  off  readily,  and  if 
they  find  lodgment  on  unoccupied  soil,  they  grow  readily 
into  new  plants.  Sometimes  they  are  carried  moderate 
distances  by  wind  or  water,  and  if  the  ground  slopes,  they 
may  easily  roll  far  enough  to  get  started  in  new  places. 


FIG.  265.  —  Fruit  of  Smoke-Tree  (Rhus  Cotinus). 

Only  one  pedicel  bears  a  fruit,  all  the  others  are  sterile,  branched,  and  covered 
with  plumy  hairs. 

445.  Dispersal  of  Seeds.  —  Seeds  are  not  infrequently 
scattered  by  apparatus  by  which  the  plant  throws  them 
about.  More  commonly,  however,  they  depend  upon 
other  agencies,  such  as  wind,  water,  or  animals,  to  carry 
them.  Sometimes  the  transportation  of  seeds  is  due  to 


HOW    PLANTS   AKE    SCATTERED 


877 


the  structure  of  the  seeds  themselves,  sometimes  to  that 
of  the  fruit  in  which  they  are  enclosed  ;  the  essential 
point  is  to  have  transportation  to  a  long  distance  made 
us  certain  as  possible,  to  avoid  overcrowding. 

446.  Explosive   Fruits.  —  Some  dry  fruits  burst   open 
when  ripe  in  such  a  way  as  to  throw  their  seeds  violently 
about.      Interesting 

studies  may  be  made, 
in  the  proper  season, 
of  the  fruits  of  the 
common  blue  violet, 
the  pansy,  the  wild 
balsam,  the  garden 
balsam,  the  crane's- 
bill,  the  herb  Robert, 
the  witch-hazel,  the 
Jersey  tea,  and  some 
other  common  plants. 

The     Capsule     Of     the      FIG.  266. -Fruits  of  Linden,  with  a  Bract  joined 

to  the  Peduncle  and  forming  a  Wing. 

tropical  American 

sand-box  tree  bursts  open  when  thoroughly  dry  with  a  noise 

like  that  of  a  pistol  shot. 

447.  Winged  or  Tufted  Fruits  and  Seeds.  —  The  fruits 
of  the  ash,  box-elder,  elm,  maple  (Fig.  169),  and  many 
other  trees,  are  provided  with  an  expanded  membranous 
wing.    Some  seeds,  as  those  of  the  catalpa  and  the  trumpet- 
creeper,    are    similarly    appendaged.     The    fruits    of   the 
dandelion,  the  thistle  (Fig.  267),  the  fleabane,  and  many 
other  plants  of  the  group  to  which  these  belong,  and  the 
seeds  of  the  willow,  the  milkweed  (Fig.  267),  the  willow- 
herb,  and  other  plants,  bear  a  tuft  of  hairs. 


378 


FOUNDATIONS   OF   BOTANY 


The  student  should  be  able,  from  his  own-  observations  on 
the  falling  fruits  of  some  of  the  trees  and  other  plants  above 
mentioned,  to  answer  such  questions  as  the  following  : 

What  is  the  use  of 
the  wing-like  append- 
ages? of  the  tufts  of 
hairs  ? 

Which  set  of  con- 
trivances seems  to  be 
the  more  successful  of 
the  two  in  securing 
this  object? 

What  particular 
plant  of  the  ones  avail- 
able for  study  seems 
to  have  attained  this 
object  most  perfectly  ? 

What  is  one  reason 
why  many  plants  with 
tufted  fruits,  such  as 
the  thistle  and  the  dan- 
delion, are  extremely 
troublesome  weeds? 

A  few  simple  experi- 
ments, easily  devised 
by  the  student,  may 
help  him  to  find  an- 

FIG.  267.  —  Winged  Fruits  of  Thistle  ;  Winged  Seeds      swers  to  the  questions 
of  Milkweed.  above  given.1 

448.  Tumble  weeds.  —  Late  in  the  autumn,  fences,  par- 
ticularly on  prairie  farms  that  are  not  carefully  tilled,  often 
serve  as  lodging-places  for  immense  numbers  of  certain 
dried-up  plants  known  as  tumbleweeds.  These  blow 
about  over  the  level  surface  until  the  first  snow  falls  and 


See  Kerner  and  Oliver,  Vol.  II,  pp.  833-875 ;  also  Seal's  Seed  Dispersal 


HOW   PLANTS   ARE   SCATTERED 


379 


even  after  that  (Fig.  269),  often  traveling  for  many  miles 
before  they  come  to  a  stop,  and  rattling  out  seeds  as  they 
go.  Some  of  the  commonest  tumbleweeds  are  the  Russian 
thistle  (Fig.  268),  the  pigweed  ( Amarantus  albus,  Fig.  269), 
the  tickle-grass  (Fig.  270),  and  a  familiar  pepper-grass 
(Lepidium).  In  order  to  make  a  successful  tumble  weed,  a 
plant  must  be  pretty  nearly  globular  in  form  when  fully 
grown  and  dried,  must  be  tough  and  light,  must  break  off 
near  the  ground,  and  drop  its  seeds  only  a  few  at  a  time 
as  it  travels.  A  single  plant 
of  Russian  thistle  is  some- 
times as  much  as  three  feet 
high  and  six  feet  in  diameter 
and  carries  not  less  than  two 
hundred  thousand  seeds. 

449.  Many -Seeded  Pods 
with  Small  Openings.— 
There  are  many  fruits  which 
act  somewhat  like  pepper- 
boxes. The  capsule  of  the 
poppy  is  a  good  instance  of 
this  kind,  and  the  fruit  of 
lily,  monkshood  (Fig.  168), 
columbine,  larkspur,  and 
jimson  weed  (Fig.  271)  acts 
in  much  the  same  way. 
Clamping  the  dry  peduncle 
of  any  one  of  these  ripe 
fruits,  so  as  to  hold  it  up- 
right above  the  table-top,  and  then  swinging  it  back  and 
forth,  will  readily  show  its  efficiency  in  seed  dispersal. 


FIG.  268.  —Russian  Thistle. 


380 


FOUNDATIONS   OF   BOTANY 


450,  Study  of  Transportation  by  Water.  —  Nothing  less 
than  a  long  series  of  observations  by  the  pond-margin  and 
the  brookside  will  suffice  to  show  how  general  and  impor 


FIG.  269.  —  Tumbleweeds  *  lodged  against  a  Wire  Fence  in  Winter. 

tant  is  the  work  done  by  water  in  carrying  the  seeds  of 
aquatics.  An  experiment  will,  however,  throw  some  light 
on  the  subject. 

EXPERIMENT   XL 

Adaptation  for  Transportation  by  Water.  —  Collect  fruits  of  as 
many  aquatic,  semi-aquatic,  or  riverside  and  brookside  species  of 
plants  as  possible,  place  them  on  shallow  pans  of  water  and  notice 
what  proportion  of  all  the  kinds  studied  will  float.  Leave  them 
twenty-four  hours  or  more  and  see  whether  all  the  kinds  that  floated 
at  first  are  still  afloat.  Some  desirable  fruits  for  this  experiment 

1  Amarantus  albus. 


HOW   PLANTS    ARE   SCATTERED 


381 


are  :  aquatic  grasses,  rushes  and  sedges,  polygon  urns,  water-dock, 
bur-reed,  arrowhead,  water-plantain,  pickerel-weed,  alder,  button- 
bush,  water-parsnip  (Sium),  water-hemlock  (Cfcwta),  water  penny- 
wort (Hydrocotyle). 

451.  Distances  traversed  by  Floating  Seeds.  —  Ocean 
currents  furnish  transportation  for  the  longest  journeys 
that  are  made  by  floating 

seeds.  It  is  a  well-known 
fact  that  cocoa-palms  are 
among  the  first  plants  to 
spring  up  on  newly  formed 
coral  islands.  The  nuts 
from  which  these  palms 
grew  may  readily  have 
floated  a  thousand  miles 
or  more  without  injury. 
On  examining  a  cocoanut 
with  the  fibrous  husk  at- 
tached, just  as  it  fell  from 
the  tree,  it  is  easy  to  see 
how  well  this  fruit  is 
adapted  for  transportation 
by  water.  There  are  al- 
together about  a  hundred 
drifting  fruits  known,  one 
(the  Maldive  nut)  reach- 
ing a  Weight  Of  twenty  tO  FIG.  270.  — Panicle  of  Tickle-Grass,  a 

Common  Tumbleweed. 

twenty-five  pounds. 

452.  Burs.  —  A  large  class  of  fruits  is  characterized  by 
the  presence  of  hooks  on  the  outer  surface.     These  are 
sometimes    outgrowths  from  the   ovary,  sometimes   from 


382 


FOUNDATIONS    OF    BOTANY 


the  calyx,  sometimes  from  an  involucre.  Their  office  is 
to  attach  the  fruit  to  the  hair  or  fur  of  passing  animals. 
Often,  as  in  sticktights  (Fig.  272),  the  hooks  are  compara- 
tively weak,  but  in  other  cases,  as  in  the  cocklebur  (Fig. 
272),  and  still  more  in  the  Marty nia,  the  fruit  of  which 
in  the  green  condition  is  much  used  for  pickles,  the 
hooks  are  exceedingly  strong.  Cockleburs  can  hardly  be 
removed  from  the  tails  of  horses  and  cattle,  into  which 


li  in 

FIG.  271.  —  Three  Fruits  adapted  for  Dispersal  by  the  Shaking  Action  of  the  Wind. 
I,  celandine  ;  II,  pea ;  III,  jimson  weed  (Datura). 

they  have  become   matted,  without  cutting  out  all  the 
hairs  to  which  they  are  fastened. 

A  curious  case  of  distribution  of  this  land  occurred 
in  the  island  of  Ternate,  in  the  Malay  Archipelago.  A 
buffalo  with  his  hair  stuck  full  of  the  needle-like  fruits  of 
a  grass1  was  sent  as  a  present  to  the  so-called  King  of 
Ternate.  Scattered  from  the  hair  of  this  single  animal, 
the  grass  soon  spread  over  the  whole  island. 

* 

1  Andropogon  acicularis. 


HOW   PLANTS   ARE   SCATTERED 


383 


Why  do  bur-bearing  plants  often  carry  their  fruit  until 
late  winter  or  early  spring? 

What  reason  can  be  given  for  the  fact  that  the  burdock, 
the  cocklebur,  the  beggar's-ticks,  the  hound's-tongue,  and 
many  other  common  burs,  are  among  the  most  persistent 
of  weeds  ? 

453.  Uses  of  Stone  Fruits  and  of  Fleshy  Fruits  to  the 
Plant.  —  Besides  the  dry  fruits,  of  which  some  of  the 
principal  kinds  have  been  mentioned,  there  are  many  kinds 


FIG.  272.  — Burs. 

A,  sticktights  ;  B,  sticktiglits,  two  segments,  magnified  ; 
C,  burdock  ;  Z>,  cockleburs. 

of  stone  fruits  and  other  fleshy  fruits  (Sects.  242-247). 
Of  these  the  great  majority  are  eatable  by  man  or  some  of 
the  lower  animals,  and  oftentimes  the  amount  of  sugar 
and  other  food  material  which  they  contain  is  very  con- 
siderable. It  is  a  well-recognized  principle  of  botany,  and 


384 


FOUNDATIONS    OF   BOTANY 


of  zoology  as  well,  that  plants  and  animals  do  not  make 
unrewarded  outlays  for  the  benefit  of  other  species.  Evi- 
dently the  pulp  of  fruits  is  not  to  be  consumed  or  used 


IV 


FIG.  273.  —Barbs  and  Hooks  of  Burs. 


I,  barbed  points  from  fruit  of  beggar's-ticks,  magnified  eleven  times ; 
II,  hook  of  cocklebur,  magnified  eleven  times ;  III,  beggar's-ticks 
fruit,  natural  size  ;  IV,  cocklebur  hook,  natural  size. 

as  food  by  the  plant  itself  or  (in  general)  by  its  seeds.  It 
is  worth  while,  therefore,  for  the  student  to  ask  himself 
some  such  questions  as  these  : l 

(1)  Why  is  the  pulp  of  so  many  fruits  eatable  ? 

(2)  Why  are  the  seeds  of  many  pulpy  fruits  bitter  or 
otherwise  unpleasantly  flavored,  as  in  the  orange  ? 

(3)  Why  are  the  seeds  or  the  layers  surrounding  the 

1  See  Kerner  and  Oliver's  Natural  History  of  Plants,  Vol.  II,  pp.  442-450. 


HOW    PLANTS    ARE    SCATTERED 


385 


seeds   of  many  pulpy  fruits  too  hard  to  be  chewed,  or 
digested,  as  in  the  date  and  the  peach? 

(4)  Why  are  the  seeds  of  some  pulpy  fruits  too  small 
to  be  easily  chewed,  and  also  indigestible,  as  in  the  fig 
and  the  currant? 

(5)  Account  for  the  not  infrequent  presence  of  currant 
bushes  or  asparagus  plants  in  such  localities  as  the  forks 
of  large  trees,  sometimes  at  a  height  of  twenty,  thirty,  or 
mpre  feet  above  the  ground  (Fig.  274). 

Careful  observation  of  the  neighborhood  of  peach,  plum, 
cherry,  or  apple  trees  at  the  season  when  the  fruit  is  ripe 
and  again  during  the  following  spring,  and  an  examina- 
tion into  the  distribution  of  wild 
apple  or  pear  trees  in  pastures 
where  they  occur,  will  help  the 
student  who  can  make  such  ob- 
servations to  answer  the  preced- 
ing questions.     So,  too,  would 
an  examination  of  the  habits  of 
fruit-eating  quadrupeds  and  of 
the  crop   and  gizzard  of  fruit- 
eating  birds  during  the  season 
when  the  fruits  upon  which  they 
feed  are  ripe. 

454.  Seed-Carrying  purposely 
done  by  Animals.  —  In  the  cases 
referred  to  in  the  preceding  sec- 
tions, animals  have  been  seen 
to  act  as  unconscious  or  even  unwilling  seed-carriers. 
Sometimes,  however,  they  carry  off  seeds  with  the  plan 
of  storing  them  for  food.  Ants  drag  away  with  them  to 


FIG.  274.  —  Red  Rasp- 
berry Bush,  in  Fork 
of  a  Maple. 


386 


FOUNDATIONS   OF   BOTANY 


their  nests  certain  seeds  which  have   fleshy  growths    on 
their  outer  surfaces.      Afterwards  they  eat  these  fleshy 


FIG.  275.  —  Red  Cedar  Trees  planted  by  Birds  roosting  on  Fences. 

parts  at  their  leisure,-  leaving  the  seed  perfectly  fit  to 
grow,  as  it  often  does.1 

Squirrels  and  bluejays   are  known  to  carry  nuts  and 
acorns    about    and   bury   them   for   future    use.       These 


FIG.  276.  —  Seed  of  Bloodroot  with  Caruncle  or  Crest,  which  serves  as  a  Handle 
for  Ants  to  hold  on  to.    Ant  ready  to  take  the  seed. 

deposits  are  often  forgotten  and  so  get  a  chance  to  grow, 
and  in  this  way  a  good  deal  of  tree-planting  is  done. 

i  See  Beal's  Seed  Dispersal,  pp.  69,  70. 


CHAPTER   XXX 

THE    STRUGGLE    FOR    EXISTENCE   AND    THE    SURVIVAL 
OF    THE    FITTEST1 

455.  Weeds.  —  Any  flowering  plant  which  is  trouble- 
some to  the  farmer  or  gardener  is  commonly  known  as  a 
weed.  Though  such  plants  are  so  annoying  from  their 
tendency  to  crowd  out  others  useful  to  man,  they  are  of 
extreme  interest  to  the  botanist  on  account  of  this  very 
hardiness.  The  principal  characteristics  of  the  most  suc- 
cessful weeds  are  their  ability  to  live  in  a  variety  of  soils 
and  exposures,  their  rapid  growth,  resistance  to  frost, 
drought,  and  dust,  their  unfitness  for  the  food  of  most  of 
the  larger  animals,  in  many  cases  their  capacity  to  accom- 
plish self-pollination,  in  default  of  cross-pollination,  and 
their  ability  to  produce  many  seeds  and  to  secure  their 
wide  dispersal.  Not  every  weed  combines  all  of  these 
characteristics.  For  instance,  the  velvet-leaf  or  butter- 
print,2  common  in  cornfields,  is  very  easily  destroyed  by 
frost ;  the  pigweed  and  purslane  are  greedily  eaten  by  pigs, 
and  the  ragweed  by  some  horses.  The  horse-radish  does 
not  usually  produce  any  seeds. 

It  is  a  curious  fact  that  many  plants  which  have  finally 
proved  to  be  noxious  weeds  have  been  purposely  intro- 
duced into  the  country.  The  fuller's  teasel,  melilot, 
horse-radish,  wild  carrot,  wild  parsnip,  tansy,  oxeye  daisy, 

1  See  Darwin's  Origin  of  Species,  Chapters  III  and  IV. 

2  Abutilon  Avicennse. 

387 


388  FOUNDATIONS   OF   BOTANY 

and  field-garlic  are  only  a  few  of  the  many  examples  of 
very  troublesome  weeds  which  were  at  first  planted  for 
use  or  for  ornament. 

456.  Study  of  Weeds.  —  Select  two  or  more  out  of  the 
following  list  of  weeds  and  report  on  the  qualities  which 
make  them  troublesome  from  the  farmer's  point  of  view 
(successful  from  their  own).1 

LIST    OF   WEEDS2 

1.  Barn-grass,*  Panicum  Crus-galli. 

2.  Beggar's  lice,*  Cynoglossum  officinale. 

3.  Beggar's-ticks,  Bidens  frondosa. 

4.  Black  mustard,*  Brassica  nigra. 

5.  Blue  thistle,*  Echium  vulgare. 

6.  Buffalo  bur,  Solanum  rostratum. 

7.  Burdock,*  Arctium  Lappa. 

8.  Buttercup,*  Ranunculus  bulbosus. 

9.  Butterweed,*  Erigeron  canadensis. 

10.  Carpet  weed,  Mollugo  verticillata. 

11.  Charlock,*  Brassica  Sinapistrum. 

12.  Chess  or  cheat,*  Bromus  secalinus. 

13.  Chickweed,  Stellaria  media. 

14.  Chicory,*  Cichorium  Intybus. 

15.  Clover  dodder,*  Cuscuta  Trifolii. 

16.  Cocklebur,*  Xanthium  spinosum. 

17.  Corn  cockle,*  Agrostemma  Git  ha  go. 

1  This  study  will  be  of  little  value  in  city  schools,  since  the  plants  should 
be  examined  as  they  grow.     Specimens  of  the  mature  weed  and  of  its  fruits 
and  seeds  may  be  preserved  by  the  teacher  from  one  season  to  another  for 
class  use.    Whole  specimens  of  small  plants,  such  as  purslane,  may  be  put 
into  preservative  fluid  (see  Handbook).    Ordinary  weeds,  such  as  ragweed, 
pigweed,  etc.,  may  be  pressed  and  kept  as  roughly  prepared  herbarium 
specimens,  while  such  very  large  plants  as  jimson  weed,  dock,  etc.,  may  be 
hung  up  by  the  roots  and  thus  dried. 

2  Names  marked  in  the  list  thus  *  are  those  of  plants  introduced  from 
other  countries,  mostly  from  Europe. 


THE   STRUGGLE   FOR   EXISTENCE  389 

18.  Cow  herb,*  Saponaria  Vaccaria. 

19.  Daisy,  oxeye,*  Chrysanthemum  Leucanthemum. 

20.  Dandelion,*  Taraxacum  officinale. 

21.  Dock,  Rumex  crispus. 

22.  Dog  fennel,*  Anthemis  cotula. 

23.  Fox-tail  grass,*  Setaria  glauca. 

24.  Horse-nettle,  Solarium  carolinense. 

25.  Jamestown  weed  or  Jimson  weed,*   Datura  Stramonium 

or  D.  Tatula. 

26.  Johnson  grass,  Andropogon  halepen'sis. 

27.  Mallow,*  Malva  rotundifolia. 

28.  Milkweed,  Asclepias  Cornuti. 

29.  Nettle,  Urtica  gracilis. 

30.  Pigweed,*  Amarantus  retroflexus. 

31.  Pigweed,*  Chenopodium  album. 

32.  Plantain,*  Plantago  major. 

33.  Pokeberry,  Phytolacca  decandra. 

34.  Purslane,  Portulaca  oleracea. 

35.  Quick-grass,*  Witchgrass,  Acjropyrum  repens. 

36.  Ragweed,  Ambrosia  artemisicefolia. 

37.  Rib  grass,*  Plantago  lanceolata. 

38.  Sand  bur,  Cenchrus  tribuloides. 

39.  Shepherd's  purse,*  Capsella  Bursa-pastoris. 

40.  Smartweed,  Polygonum  Hydropiper. 

41.  Sorrel,*  Rumex  Acetosella. 

42.  Spanish  needles,  Bidens  bipinnata. 

43.  Sticktights,  Desmodium  canadense. 

44.  Thistle,*  Cirsium  lanceolatum,  C.  arvense. 

45.  Yarrow,  Achillea  Millefolium. 

457.  Origin  of  Weeds.1  —  By  far  the  larger  proportion 
of  our  weeds  are  not  native  to  this  country.  Some  have 
been  brought  from  South  America  and  from  Asia,  but 
most  of  the  introduced  kinds  come  from  Europe.  The 
importation  of  various  kinds  of  grain  and  of  garden-seeds, 

1  See  the  article  "  Pertinacity  and  Predominance  of  Weeds,"  in  Scientific 
Papers  of  Asa  Gray,  selected  by  C.  S.  Sargent,  Vol.  II,  pp.  234-242. 


390  FOUNDATIONS   OF   BOTANY 

mixed  with  seeds  of  European  weeds,  will  account  for  the 
presence  of  many  of  the  latter  among  us.  Others  have 
been  brought  over  in  the  ballast  of  vessels.  Once  landed, 
European  weeds  have  succeeded  in  establishing  themselves 
in  so  many  cases,  because  they  were  superior  in  vitality 
and  in  their  power  of  reproduction  to  our  native  plants. 
This  may  not  improbably  be  due  to  the  fact  that  the  Euro- 
pean and  western  Asiatic  vegetation,  much  of  it  consisting 
from  very  early  times  of  plants  growing  in  comparatively 
treeless  plains,  has  for  ages  been  habituated  to  flourish  in 
cultivated  ground  and  to  contend  with  the  crops  which 
are  tilled  there. 

458,  Plant  Life  maintained  under  Difficulties.  —  Plants 
usually  have  to  encounter  many  obstacles  even  to  their 
bare  existence.  For  every  plant  which  succeeds  in  reach- 
ing maturity  and  producing  a  crop  of  spores  or  of  seeds 
there  are  hundreds  or  thousands  of  failures,  as  it  is  easy 
to  show  by  calculation.  The  morning-glory  (Ipomoea  pur- 
purea)  is  only  a  moderately  prolific  plant,  producing,  in 
an  ordinary  soil,  somewhat  more  than  three  thousand 
seeds.1  If  all  these  seeds  were  planted  and  grew,  there 
would  be  three  thousand  plants  the  second  summer,  sprung 
from  the  single  parent  plant.  Suppose  each  of  these 
plants  to  bear  as  the  parent  did,  and  so  on.  Then  there 
would  be  : 

9,000,000  plants  the  third  year. 
27,000,000,000  plants  the  fourth  year. 
81,000,000,000,000  plants  the  fifth  year. 
243,000,000,000,000,000  plants  the  sixth  year. 
729,000,000,000,000,000,000  plants  the  seventh  year. 

1  Rather  more  than  three  thousand  two  hundred  by  actual  count  and 
estimation. 


THE   STRUGGLE   FOR   EXISTENCE  391 

It  is  not  difficult  to  see  that  the  offspring  of  a  single 
morning-glory  plant  would,  at  this  rate,  soon  actually 
cover  the  entire  surface  of  the  earth.  The  fact  that 
morning-glories  do  not  occupy  any  larger  amount  of  ter- 
ritory than  they  do  must  therefore  depend  upon  the  fact 
that  the  immense  majority  of  their  seeds  are  not  allowed 
to  grow  into  mature  plants. 

There  are  many  plants  which  would  yield  far  more  sur- 
prising results  in  a  calculation  similar  to  that  just  given 
than  are  afforded  by  the  morning-glory.  For  instance,  a 
foxglove  capsule  contains  011  an  average  nearly  1800 
seeds.  A  small  foxglove  plant  bears  from  140  to  200  cap- 
sules and  a  large  one  from  530  to  700.  Therefore  a  single 
plant  may  produce  over  1,250,000  seeds.  A  single  orchid 
plant1  has  been  shown  to  produce  over  10,000,000  seeds. 

459.  Importance  of  Dispersal  of  Seeds.  —  It  is  clear  that 
any  means  of  securing  the  wide  distribution  of  seeds  is  of 
vital  importance  in  continuing  and  increasing  the  numbers 
of  any  kind  of  plant,  since  in  this  way  destruction  by  over- 
crowding and  starvation  will  be  lessened. 

A  few  of  the  means  of  transportation  of  seeds  have  been 
described  in  Sects.  445-454,  but  the  cases  are  so  numerous 
and  varied  that  a  special  treatise  might  well  be  devoted  to 
this  subject  alone. 

460.  Destruction  of  Plants  by  Unfavorable  Climates.  - 
Land-plants,  throughout  the  greater  part  of  the  earth's 
surface,  are  killed  in  enormous  numbers  by  excessive  heat 
and  drought,  by  floods,  or  by  frost.     After  a  very  dry 
spring  or  summer  the  scantiness  of  the  crops,  before  the 
era  of  railroads  which  nowadays  enable  food  to  be  brought 

1  Maxillaria,  see  Darwiu's  Fertilization  of  Orchids,  Chapter  IX. 


392  FOUNDATIONS   OF  BOTANY 

in  rapidly  from  other  regions,  often  produced  actual  fam- 
ine. Wild  plants  are  not  observed  so  carefully  as  culti- 
vated ones  are,  but  almost  every  one  has  no'ticed  the 
patches  of  grass,  apparently  dead,  in  pastures  and  the 
withered  herbaceous  plants  everywhere  through  the  fields 
and  woods  after  a  long  drought. 

Floods  destroy  the  plants  over  large  areas,  by  drowning 
them,  by  sweeping  them  bodily  away,  or  by  covering  them 
with  sand  and  gravel. 

Frosts  kill  many  annual  plants  before  they  have  ripened 
their  seeds,  and  severe  and  changeable  winters  sometimes 
kill  perennial  plants. 

461.  Destruction  by  Other   Plants Overcrowding  is 

one  of  the  commonest  ways  in  which  plants  get  rid  of 
their  weaker  neighbors.     If  the  market-gardener  sows  his 
lettuce  or  his  beets  too  thickly,  few  perfect  plants  will  be 
produced,  and  the  same  kind  of  effect  is  brought  about  in 
nature  on  an  immense  scale.     Sometimes  plants  are  over- 
shadowed and  stunted  or  killed  by  the  growth  all  about 
them  of  others  of  the  same  kind ;  sometimes  it  is  plants 
of  other  kinds  that  crowd  less  hardy  ones  out  of  existence. 

Whole  tribes  of  parasitic  plants,  some  comparatively 
large,  like"  the  dodder  and  the  mistletoe,  others  micro- 
scopic, like  blights  and  mildews,  prey  during  their  whole 
lives  upon  other  plants. 

462.  Adaptations  to   meet  Adverse   Conditions.  —  Since 
there  are  so  many  kinds  of  difficulties  to  be  met  before  the 
seed  can  grow  into  a  mature  plant  and  produce  seed  in  its 
turn,  and  since  the  earth's  surface   offers  such  extreme 
variations  as  regards  heat,  sunlight,  rainfall,  and  quality 
of   soil,  it  is  evident  that  there   is   a  great  opportunity 


THE    STRUGGLE   FOR    EXISTENCE  393 

offered  for  competition  among  plants.  Of  several  plants 
of  the  same  kind,  growing  side  by  side,  where  there  is 
room  for  but  one  full-grown  one,  all  may  be  stunted,  or 
one  may  develop  more  rapidly  than  the  others,  starve  them 
out,  and  shade  them  to  death.  Of  two  plants  of  different 
kinds  the  hardier  will  crowd  out  the  less  hardy,  as  ragweed, 
pigweed,  and  purslane  do  with  ordinary  garden  crops. 
Weeds  like  these  are  rapid  growers,  stand  drought  or 
shade  well,  will  bear  to  be  trampled  on,  and,  in  general, 
show  remarkable  toughness  of  organization. 

Plants  which  can  live  under  conditions  that  would  be 
fatal  to  most  others  will  find  much  less  competition  than 
the  rank  and  file  of  plants  are  forced  to  encounter.  Lichens, 
growing  on  barren  rocks,  are  thus  situated,  and  so  are  the 
fresh-water  plants,  somewhat  like  pond-scum  in  their  struc- 
ture, which  are  found  growing  in  hot  springs  at  tempera- 
tures of  140°,  or  in  some  cases  nearly  up  to  200°. 

463,  Examples  of  Rapid  Increase. — Nothing  but  the 
opposition  which  plants  encounter  from  overcrowding  or 
from  the  attacks  of  their  enemies  prevents  any  hardy  kind 
of  plant  from  covering  all  suitable  portions  of  a  whole 
continent,  to  the  exclusion  of  most  other  vegetable  life. 
New  Zealand  and  the  pampas  of  La  Plata  and  Paraguay, 
in  South  America,  have,  during  the  present  century,  fur- 
nished wonderful  examples  of  the  spread  of  European 
species  of  plants  over  hundreds  of  thousands  of  square 
miles  of  territory.  The  newcomers  were  more  vigorous, 
or  in  some  way  better  adapted  to  get  on  in  the  world 
than  the  native  plants  which  they  encountered,  and  so 
managed  to  crowd  multitudes  of  the  latter  out  of 
existence. 


394  FOUNDATIONS    OF   BOTANY 

In  our  own  country  a  noteworthy  case  of  the  kind  has 
occurred  so  very  recently  that  it  is  of  especial  interest 
to  American  botanists.  The  so-called  Russian  thistle 
(Fig.  268),  which  is  merely  a  variety  of  the  saltwort,  so 
common  along  the  Atlantic  coast,  was  first  introduced  into 
South  Dakota  in  flaxseed  brought  from  Russia  and  planted 
in  1873  or  18 74.  In  twenty  years  from  that  time  the  plant 
had  become  one  of  the  most  formidable  weeds  known,  over 
an  area  of  about  twenty-five  thousand  square  miles. 

464.  Importance  of  Adapt! veness  in  Plants.  —  It  may  be 
inferred  from  the  preceding  sections  that  a  premium  is  set 
on  all  changes  in  structure  or  habits  which  may  enable 
plants  to  resist  their  living  enemies  or  to  live  amid  partially 
adverse  surroundings  of  soil  or  climate.     It  would  take  a 
volume  to  state,  even  in  a  very  simple  way,  the  conclusions 
which  naturalists  have  drawn  from  this  fact  of  a  savage 
competition  going  on  among  living  things,  and  it  will  be 
enough  to  say  here  that  the  existing  kinds  of  plants  to  a 
great  degree  owe  their  structure  and  habits  to  the  operation 
of  the  struggle  for  existence,  this  term  including  the  effort  to 
respond  to  changes  in  the  conditions  by  which  they  are  sur- 
rounded.    How  the  struggle  for  existence  has  brought 
about  such  far-reaching  results  will  be  briefly  indicated  in 
the  next  section. 

465.  Survival  of  the   Fittest.  —  When  frost,  drought, 
blights,  or  other  agencies  kill  most  of  the  plants  in  any 
portion  of  the  country,  it  is  often  the  case  that  many  of 
the  plants  which  escape  do  so  because  they  can  stand  more 
hardship  than  the  ones  which  die.     In  this  way  delicate 
individuals  are  weeded  out  and  those  which   are   more 
robust  survive.    But  other  qualities  besides  mere  toughness 


THE   STRUGGLE   FOR   EXISTENCE  395 

often  decide  which  plant  or  plants  of  any  particular 
kind  shall  live  and  which  ones  shall  die  out.  In  every 
grove  of  oaks  there  are  some  with  sweeter  and  others  with 
more  bitter  acorns.  One  shellbark  hickory  bears  nuts 
whose  shell  is  easily  cracked  by  hogs,  while  another  pro- 
tects its  seeds  by  a  shell  so  hard  that  it  is  cracked  only 
by  a  pretty  heavy  blow.  In  case  of  all  such  differences, 
there  is  a  strong  tendency  to  have  the  less  eatable  fruit  or 
seed  preserved  and  allowed  to  grow,  while  the  more  eat- 
able varieties  will  be  destroyed.  Some  individuals  of  the 
European  holly  produce  bright  red  berries,  while  others 
produce  comparatively  inconspicuous  yellow  ones.  It  has 
been  found  that  the  red  berries  are  much  more  promptly 
carried  off  by  birds,  and  the  seeds  therefore  much  more 
widely  distributed  than  the  yellow  ones  are.  The  result 
of  this  kind  of  advantage,  in  any  of  its  countless  forms,  is 
sometimes  called  survival  of  the  fittest,  and  sometimes 
natural  selection.  The  latter  name  means  only  that  the 
outcome  of  the  process  just  described,  as  it  goes  on  in 
nature,  is  much  the  same  as  that  of  the  gardener's  selection, 
when,  by  picking  out  year  by  year  the  earliest  ripening 
peas  or  certain  kinds  of  the  oddest-colored  chrysanthe- 
mums, he  obtains  permanent  new  varieties.  Natural 
agencies,  acting  on  an  enormous  scale  through  many 
ages,  may  well  be  supposed  to  have  brought  about  the 
perpetuation  of  millions  of  such  variations  as  are  known 
to  be  of  constant  occurrence  among  plants,  wild  as  well 
as  cultivated. 


INDEX 


Starred  page-numbers  indicate  where  cuts  occur. 


PARTS  I  AND  II 


Absorption  of  carbon  dioxide,  166- 
170. 

Acacia,  leaf  of,  *145. 

Accessory  buds,  122,  *123. 

Accessory  fruits,  *226. 

Acuminate,  *131. 

Acute,  *131. 

Adaptations  to  conditions  of  exist- 
ence, 394. 

Adherent,  204. 

Adnate,  204. 

Adventitious  buds,  128. 

Adventitious  roots,  36. 

Aerial  roots,  36,  *37,  *38,  *3<J. 

Agaricus,  study  of,  264-266*. 

Age  of  trees,  71. 

Aggregate  fruits,  225,  *226. 

Ailanthus  twig,  *121. 

Air,  relation  to  germination,  10- 
12. 

Air  chamber,  *151,  *153,  *154. 

Air-passages  in  Hippurisstem,*173. 

Akene,  *222. 

Albuminous  substances,  22. 

Alg33,  232,  241-257*. 

Algae,  classification  of,  *257. 

Algae,  study  of,  241-257*. 


Alternate,  *65,  66. 

Alternate  leaves,  *140. 

Alternation  of  generations,  278. 

Althaea  leaf,  *152. 

Anatomy  of  plants  (see  under  root, 

stem,  leaf,  flower,  fruit,  structure 

of). 

Angiosperms,  233. 
Angiosperins,  oldest,  304,  305. 
Animal  food,  need  of,  344. 
Animals,    defenses    against,    345- 

352*. 

Annual  growth,  indefinite,  69. 
Annual  ring,  *100,  *101. 
Annuals,  71. 
Anther,  201,  202,  *203. 
Anther,  modes  of  opening,  *211. 
Antheridia,  *284,  285. 
Antherozoids,  247,  248,  *251,  254. 

*279,  *284. 
Antipodal  cells,  *215. 
Ant-plants,  346,  *347. 
Ants  plant  seeds,  *386. 
Apetalous,  *198. 
Apothecia,  271. 
Apple  leaf,  stipules  of,  *135. 
Aquatic  roots,  37. 


397 


398 


FOUNDATIONS   OF  BOTANY 


Arch  of  hypocotyl,  25-27. 
Archegonia,  *284,  285,  *295. 
Arctic  willow,  *328. 
Aristolochia  stem,  bundle  of,  *88. 
Aristolochia  stem,  cross-section  of, 

*87,  88. 

Arrangement  of  leaves,  *140,  *141 . 
Arrow-shaped,  *132. 
Asci,  263,  270,  273. 
Ascomycetes,  232. 
Asexual  generation,  278. 
Ash  tree,  naturally  grafted,  *99. 
Asparagus,  79,  *80. 
Aspidium,  *288. 
Asplenium,  study  of,  286-289*. 
Assimilation,  171,  172. 
Autumn  leaves,  coloration  of,  176. 
Axillary  bud,  *122. 
Axillary  flowers,  *186. 

Bacillariales,  232. 

Bacilli,  *237. 

Bacteria,  232,  *237. 

Bacteria,  manufacture  of  nitric  acid 

by.  340. 

Bacteria,  study  of,  238,  239. 
Barbed  hairs,  *351. 
Barberry,  spiny  leaves  of,  *348. 
Bark,  86,  *91,  104. 
Basidia,  *266. 
Basidiomycetes,  232. 
Bast,  *87,  *91,  *92. 
Bast-bundle,  *92. 
Bean-pod,  study  of,  219. 
Bean  seed,  7,  8. 
Beech  twig,  64. 

Beech-wood,  cross-section  of,  *101. 
Bees,  355,  *356,  *360. 
Beet  leaf,  *151. 
Beggar's  ticks,  *384. 
Begonia  leaf,  osmose  in,  51. 


Bell-shaped,  *202. 

Belt's  bodies,  *347. 

Berry,  *225. 

Berry,  study  of,  217. 

Biennial,  47,  71. 

Biogenesis,  law  of,  299,  300. 

Birch,  branching  of,  *71. 

Bird-pollinated  flowers,  302. 

Birds  plant  seeds,  385,  *386. 

Black  mould,  study  of,  257,   258. 

259. 

Bladder-wrack,  *250. 
Botanical  geography,  324-335. 
Botanical    geography     of    United 

States,  333-335. 
Botany,  definition  of,  1. 
Box-elder,  buds  of,  *123. 
Box-elder,  radial  and  cross-sections 

of  stem  of,  *89. 
Bract,  *186,  187. 
Branches  formed  from  adventitious 

buds,  128. 

Branching,  alternate,  *65,  66. 
Branching   and   leaf-arrangement, 

64,  65. 

Branching,  opposite,  *65. 
Branch-spine,  *69. 
Brazil  nut,  food  stored  in,  23,  24. 
Breathing-pore,  *153. 
Bryophytes,  232,  277,  278. 
Buckeye,  bud  of,  *120. 
Bud,  horse-chestnut,  119,  120. 
Bud-scales,  121. 
Buds,  118-129. 
Buds,  adventitious,  128. 
Buds,  dormant,  127,  128. 
Buds,  naked,  121. 
Buds,  position  of,  121,  *122,  *123, 

*124. 

'Buds,  structure  of,  119,  *125. 
Bulb,  77,  *79. 


INDEX 


399 


Bulb,  hyacinth,  *79. 

Bulb,  onion,  77. 

Bulblets,  375,  376. 

Bulrush,  cross-section  of  stem  of, 

*84. 

Burs,  381,  382,  *383. 
Buttercup,  leaf  of,  *135. 
Buttercup,  study  of  flower  of,  195. 

196. 
Butternut,  buds  of,  *124. 

Cabbage,  a  bud,  123. 

Cactus,  *80,  *315. 

Cactus  flower,  transitions  in,  *208. 

Caladium,  76,  *77. 

Calyx,  *197. 

Cambium,  *87,  *88,  *89,  95-100. 

Cambium-ring,  96,  *97. 

Canna,  parallel  veining  in,  136. 

Capsule,  223. 

Carbon  dioxide,  absorption  of,  166- 

168. 
Carbon  dioxide,  disposition  of,  168, 

169. 

Carnivorous  plants,  342-344*. 
Carpel,  198. 

Castor  bean,  germination  of,  *7. 
Castor-oil  plant,    early  history  of 

stem,  *95. 
Castor-oil      plant,      fibro-vascular 

bundle  of,  *95. 
Catharinea,  *282. 
Catkin,  *187. 
Celandine,  leaf  of,  *134. 
Cell,  20,  21. 
Cell-contents,  *19,  *155,  180,  *183, 

*184. 

Cell-contents,  continuity  of,  146. 
Cell-division,  *183,  *242,  245. 
Cell-multiplication  in  pond-scum, 

*242. 


Cell-sap,  *183. 

Cell,  simplest  form  of,  178,  *179, 

180. 

Cell-wall,  178. 
Cells,  isolated  wood-,  *91. 
Cellulose,  a  compound  of  carbon, 

hydrogen,  and  oxygen ;  the  chief 

constituent  of  ordinary  cell- walls, 

156,  171,  268. 
Central  cylinder,  *42. 
Central  placenta,  *205. 
Chara,  *248,  *249. 
Characese,  249,  250. 
Chemical  changes  in  leaves  before 

falling,  175,  176. 
Cherry,   buds  in  axils  of  leaves, 

*122. 

Cherry  twig,  *63,  *125. 
Chestnut  fruit,  *222. 
Chlorophyceae,  232. 
Chlorophyll,  168,  169,  176. 
Chlorophyll  bodies,  *154,  *155. 
Cilium,  180. 
Circulation  of  protoplasm,    *184, 

185. 

Cladophyll,  79,  *81. 
Class,  231. 

Classification,  228-234. 
Cleistogainous  flowers,  369,  *370. 
Clerodendron,  *363. 
Climbing  plants,  73-75*. 
Climbing   shrubs,    stem-structure, 

99,  100. 

Climbing  stems,  *73,  *74,  *75. 
Clinostat,  *58,  59. 
Clover  leaf,  *144. 
Club-moss,  study  of,  291,  *292. 
Cluster-cup,  259,  *261. 
Coherent,  200. 
Cohesion,  204,  *205. 
Collenchyma,  *95. 


400 


FOUNDATIONS   OF   BOTANY 


Colocasia,  *77. 

Coloration  of  autumn  leaves,  176. 
Colors  of  flowers,  357,  358. 
Common  receptacle,  *189. 
Compass-plant,      nearly      vertical 

leaves  of,   *147. 
Composite  head,  188,  *189,  190. 
Compound  cyme,  *191. 
Compound  leaves,  *137,  *138,  139. 
Compound  pistil,  202. 
Compound  umbel,  *189. 
Conceptacles,  250,  *252. 
Condensed  stems,  78. 
Conifers,  wood  of,  *93,  *94. 
Coniferous  wood,  structure  of,  92, 

*93,  *94. 
Conjugate,  232. 
Conjugating  cell,  *243,  *259. 
Conjugation,  *243. 
Consolidated,  204. 
Continuity  of  protoplasm,  146. 
Contractile  vacuole,  180. 
Contractility,  182. 
Cork,  90,  *100,  104,  115. 
Conn,  a  bulb-like,  fleshy  stem,  or 

base  of  stem,  "  a  solid  bulb." 
Corn,  aerial  roots  of,  *38. 
Corn,  cross-section  of  stem  of,  *83. 
Corn,  germination  of,  8. 
Corn,  grain  of,  *16. 
Corn,  root- tip,  section,  *42. 
Corn-stem,  structure  of,  *83,  84. 
Corolla,  *197. 
Corymb,  *186,  187. 
Qotyledon,  7. 
Cotyledon,  disposition  made  of,  28, 

29. 

Cotyledons,  thickened,  use  of,  29. 
Crenate,  132. 
Cross-pollination,  353. 
Crow-berry,  rolled-up  leaf  of,  *317. 


Cryptogams,  231. 

Cryptogams,  classes  of,  232,  233. 

Cuspidate,  *131. 

Cuticle,  unequal  development  of,  by 

epidermis-cells,  156,  *157. 
Cutin,  156. 
Cutting  leaves,  *351. 
Cyme,  *191. 
Cypress,  71. 

Dahlia,  thickened  roots  of,  *41. 
Daily  movements  of  leaves,  *144, 

*145,  *146. 
Dandelion,  *72. 
Darwin,  Charles,  353. 
Date-palms,  *85. 
Datura,  stigma  of,  *213. 
Deciduous,  175. 

Defenses  against  animals,  345-352.* 
Definite  annual  growth,  69. 
Dehiscent  fruits,  222,  *223. 
Deliquescent  trunk,  66,  *67. 
Dentate,  132. 

Descent  of  water,  109,  *110. 
Desert,  Sahara,  *325. 
Desmids,  *243. 

Destruction  of  plants,  391,  392. 
Determinate  inflorescence,  191. 
Deutzia  leaves,  *142,  *143. 
Diadelphous,  202. 
Diagrams,  floral,  204,  *205,  *296. 
Diatoms,  study  of,  *240,  241. 
Dichogamy,  *363,  *364. 
Dicotyledonous  plants,  34,  233. 
Dicotyledonous  stem,  annual,  gross 

structure  of,  86,  *87. 
Dicotyledonous  stem,  cross-section 

of,  *87,  *89,  *91,  *96,  *100. 
Dicotyledonous  stem,    mechanical 

importance    of    distribution    of 

material  in,  89,  90. 


INDEX 


401 


Dicotyledonous  stem,  minute  struc- 
ture of,  86-98* 

Dicotyledonous  stem,  rise  of  water 
in,  107,  108,  *109. 

Dimorphous  flowers,  *366,  367. 

Dioecious,  200. 

Discharge  of  pollen,  *211. 

Disk-flowers,  188,  »189. 

Dispersal  of  seeds,  376-386*. 

Dispersal  of  seed-plants,  373-376. 

Distinct,  201. 

Distribution  of  material  in  mono- 
cotyledonous  stems,  *84,  85. 

Dock  fruit,  study  of,  219,  220. 

Dodder,  39,  *40,  41. 

Dormant  buds,  127,  128'. 

Double  flowers,  209. 

Drip-leaves,  *314. 

Drosera,  *341,  *342,  343. 

Drought,  endurance  of,  162,  168. 

Drought-plants,  313-317*. 

Dry  fruits,  224. 

Duckweed,  314. 

Duct,  *92. 

Earliest  plants,  298. 

Ecology,  2,  307. 

Egg,  osmosis  in,  50,  *51. 

Egg-cell,  *249,  *251,  280,  *284,  285. 

Elaters,  294. 

Elliptical,  *131. 

Elm,  *67. 

Elm  bud,  *125. 

Elm  fruit,  *223. 

Elm  leaf,  130,  133. 

Elm,  twig  of,  *125. 

Emarginate,  *131. 

Embryo,  6,  17. 

Embryo  sac,  *215. 

Endosperm,  *15,  *16,  17,  19. 

Energy,  source  of,  in  plants,  173. 


Enslaved  plants,  338,  *339. 
Epidermis,  uses  of,  156,  *157. 
Epidermis  of  root,  *42,  *44. 
Epigynous,  204,  *205. 
Epipetalous,  204,  *205. 
Epiphytes,  322,  *323. 
Equisetales,  232. 
Equiseturu,  study  of,  292-295*. 
Essential  organs,  *197. 
Euphorbia  splendens,  *350. 
Evergreen,  175. 
Evolutionary    history    of    plants, 

298-305. 

Excretion  of  water,  172,  173. 
Excurrent  trunk,  *66. 
Existence,  struggle  for,  387-393. 
Exogenous,  96. 
Explosive  fruits,  377. 

Fall  of  horse-chestnut  leaf,  *137. 
Fall  of  the  leaf,  175,  176. 
Family,  230. 

Family,  subdivisions  of,  231. 
Fascicled  roots,  *41. 
Fermentation,  269. 
Fern,  study  of,  286-289*. 
Fern-plants,  295-297. 
Ferns,  290,  291. 
Fertilization,  *214,  *215,  21«i. 
Fibrous  roots,  *41. 
Fibro-vascular  bundles,  *83. 
Ficus  elastica,  leaf  of,  *154. 
Ficus  religiosa,  drip-leaf  of,  *314. 
Fig,    transpiration   in,    160,   *161, 

162. 

Filament,  201,  202,  *203. 
Filicales,  232. 
Fir  wood,  *93. 
Fission,  *242. 
Fission-plants,  232. 
Fittest,  survival  of,  394,  395. 


402 


FOUNDATIONS   OF   BOTANY 


Flax,  cross-section  of  stem  of,  *91. 

Fleshy  fruits,  224. 

Fleshy  fruits,  uses  of,  383-385. 

Fleshy  roots,  45,  4G,  *47. 

Floating  seeds,  381. 

Floral  diagrams,  204,  *205,  *206. 

Floral  envelopes,  198. 

Floral  organs,  movements  of,  365, 

366. 

Floridese,  255. 

Flower,  nature  of,  208-211*. 
Flower,  organs  of,  *197. 
Flower,  plan  of,  197-206*. 
Flower-buds,  position  of,  186. 
Flowerless  plants,  232,  233,  235- 

297. 

Flowers,  bird-pollinated,  362. 
Flowers,  colors  of,  357,  358. 
Flowers,  ecology  of,  353-372*. 
Flowers,  odors  of,  357. 
Flytrap,  Venus,  *343,  344. 
Follicle,  *223. 
Food  in  embryo,  14. 
Food,  storage  of,  in  root,  46,  *47. 
Food,  storage  of,  in  stem,  113-117. 
Food,  storage  outside  of  embryo, 

15. 

Formative  tissue,  95. 
Fossil  plants,  298,  299. 
Fossils,  298. 
Four-o'clock  seed,  15. 
Foxglove,  pinnate  leaf  of,  *133. 
Free,  204. 

Free  central  placentation,  *205. 
Frond,  287,  *288. 
Frost,  action  of,  394. 
Fruit,  221-227*. 
Fruit,  definition  of,  221. 
Fruit-dots,  *288. 
Fruits,  study  of,  217-220. 
Fruits,  uses  of,  376-386*. 


Fucus,  250-252*. 
Funaria,  *284. 
Fungi,  232,  274-276. 

Gametophyte,  291. 

Gamopetalous,  200. 

Gamosepalous,  200. 

Gemmae,  279. 

Generations,  alternation  of,  278. 

Generative    cells,    in    pollen  tube, 

*214. 

Genus,  229. 

Geography,  botanical,  324-335. 
Geography,  botanical,  of  the  United 

States,  333-335. 
Geotropism,  *57,  *58,  59,  68. 
Germination,  5-13. 
Germination,     chemical      changes 

during,  11-13. 

Germination,  conditions  of,  8-11. 
Gills,  *264,  265. 
Gonidia,  273. 
Gourd-fruit,  224. 
Grafting,  98,  *99. 
Grain,  222. 

Grape  sugar,  test  for,  116,  117. 
Gray,  Asa,  71. 
Green  layer  of  bark,  86,  *91. 
Groups,  231. 
Growing  point,  *42. 
Growth,  measurement  of,  in  stem, 
.32. 

Growth,  secondary,  *96,  *97,  *100. 
Guard-cells,  *151,  *153,  *154,  158, 

159. 
Gymnosperms,  233. 

Hsematococcus,  *244. 
Hairs,  158. 

Hairs,  stinging,  349,  350,  *351. 
Halberd-shaped,  *132. 


INDEX 


403 


Half-parasites,  336. 

Halophytes,  311,  *319,  320,  *326. 

Hard  bast,  *87,  *91,  *92. 

Haustoria,  39. 

Head,  *188. 

Heart-shaped,  *132. 

Heartwood,  105. 

Heliotropism,  148. 

Hemlock,  lateral  extension  of 
roots,  *60. 

Hepatic*,  232,  280,  281. 

Hepaticse,  study  of,  278-280*. 

Herbs,  70. 

Hesperidium,  *225. 

High  mallow,  provisions  for  cross- 
pollination  of,  *364. 

Hilum,  6. 

Honey-bee,  leg  of,  *356. 

Honey-gland,  *357. 

Honey  locust,  spine,  *69. 

Hop,  twining  of,  *75. 

Hormogonia,  *238. 

Horse-chestnut  bud,  study  of,  119, 
120. 

Horse-chestnut,  germination,  8. 

Horse-chestnut  twig,  62-64. 

Host,  39. 

Hot  springs,  plants  in,  393. 

Hyacinth,  bulb  of,  *79. 

Hybrid,  229. 

Hybridization,  229. 

Hydrangea,  transpiration  in,  159- 
161*. 

Hydrogen,  168. 

Hydrophytes,  311,  *312,  *313, 
*314. 

Hymenium,  *265. 

Hyphse,  257,  *258. 

Hypocotyl,  6,  25-27. 

Hypocotyl,  cross-section  of,  95. 

Hypogynous,  204,  *205. 


Iceland  moss,  274. 
Imperfect  flowers,  199. 
Indefinite  annual  growth,  69. 
Indehiscent  fruits,  221,  *222. 
Indeterminate  inflorescence,  186. 
Indian  corn,  germination  of,  8. 
Indian  corn,  kernel  of,  16. 
Indian  corn,  root-tip,  *42,  43. 
Indian    corn,    structure    of    stem, 

*83,  84. 

Indian  pipe,  169. 
India-rubber  plant,  leaf  of,  *154. 
India-rubber    plant,    transpiration 

of,  160-162. 
Indusium,  287,  *288. 
Inflorescence,  186-191*. 
Inflorescence,  determinate,  191. 
Inflorescence,  diagrams  of,  *190. 
Inflorescence,  indeterminate,  186. 
Insectivorous  plants,  340-344*. 
Insect  pollination,  355-369*. 
Insect  pollination,  study   of,  367- 

369. 
Insects,  pollen-carrying  apparatus 

of,  355,  *356. 

Insects,  sense  of  smell  of,  357. 
Insects,  vision  of,  358. 
Insect-traps,  leaves  as,  *342,  *343. 
Insect  visits,  358-362*,  *365. 
Insertion  of  floral  organs,  *205. 
Intercellular  spaces,  *95. 
Internode,  32,  83. 
Involucre,  188,  *189. 
Ipomcea  Jalapa,  46. 
Ipomoea,  rate  of  increase  of,  390, 

391. 

Iris,  rootstock  of,  *77. 
Irish  moss,  253. 
Irritability  in  plants,  nature  and 

occurrence  of,  182-184. 
Ivy,  aerial  roots  of,  *39. 


404 


FOUNDATIONS   OF   BOTANY 


Keel,  *199.. 
Kidney-shaped,  *131. 
Knots,  *102. 

Labiate,  *203. 

Ladyfern,  286. 

Lanceolate,  *131. 

Lateral  buds,  63,  121. 

Leaf,  130-139*. 

Leaf,  accumulation  of  mineral 
matter  in,  165. 

Leaf-arrangement,  *140,*141,  *142, 
*143. 

Leaf-bases,  *132. 

Leaf-buds,  122,  123. 

Leaf,  fall  of,  175,  176. 

Leaf-like  stems,  78,  79,  *81. 

Leaf-margins,  *132. 

Leaf-mosaics,  142,  *143. 

Leaf-outlines,  *131. 

Leaf-sections,  *151,  *154. 

Leaf-spine,  *348. 

Leaf-stalk,  130. 

Leaf-tendril,  *138. 

Leaf -tips,  *131. 

Leaf-traces,  155. 

Leaves  as  insect-traps,  *342,  *343. 

Leaves,  compound,  *137,  *138, 139. 

Leaves  cutting,  350,  *351. 

Leaves,  divided,  143. 

Leaves,  functions  of,  155-174. 

Leaves,  movements  of,  *144,  *145, 
*146. 

Leaves,  simple,  137. 

Leaves,  structure  of,  150-158*. 

Legume,  223. 

Lemon,  study  of,  217,  218. 

Lenticels,  104. 

Leucoium,  pollen  tube  with  gener- 
ative cells,  *214. 

Lianas,  *73. 


Lichen,  232. 

Lichenes,  232. 

Lichens,  nature  of,  273,  274. 

Lichens,  study  of,  270-273*. 

Light,  exposure  to,  140-149*. 

Light,   movements    towards,    148, 

149. 

Lignin,  171,  172. 
Lily  leaf,  150. 
Lily,  pollen  grains  producing  tubes 

on  stigma,  *214. 
Limb  of  calyx  or  corolla,  200. 
Lime,  165. 

Linden,  fruit  cluster  of,  *377. 
Linden  fruit,  *377. 
Linden  wood,  structure  of,  *100. 
Linear,  *131. 
Liverworts,  277-281*. 
Living  parts  of  the  stem,  104,  105. 
Lobe,  201. 
Locules,  203. 
Locust,  piunately   compound   leaf 

of,  *138. 

Locust,  thorn-stipules  of,  350. 
Luffa,  86. 
Lupine,  white,  8. 
Lycopodiales,  232. 
Lycopodium,  study  of,  291,  *292. 

Macrospores,  291,  *302. 

Macrosporophyll,  302. 

Magnolia,  forking  of,  *70,  *71. 

Mahogany  wood,  structure  of,  *101 . 

Maldive  nut,  381. 

Mallows,  pollination  in,  364. 

Malt,  13. 

Maltose,  116. 

Mangrove,  *319. 

Maple  fruit,  *223. 

Maple  leaf,  134. 

Marchantia,  study  of,  278-281*. 


INDEX 


405 


Marestail,  air-passages  of,  *173. 
Mechanics    of    monocotyledonous 

stems,  *84,  85. 
Medullary  ray,  45,  *101. 
Melon,     palmately     netted-veined 

leaf  of,  *133. 
Melon-cactus,  78,  *80. 
Messmates,  340. 
Mesophytes,  317,  318. 
Mesquite,  root-system  of,  48. 
Metabolism,  165-176. 
Metabolism,  digestive,  172. 
Micropyle,  6. 

Microsphsera,  study  of,  263,  264. 
Microspores,  *302. 
Microsporophyll,  302. 
Midrib,  *133. 

Mildews,  powdery,  263,  *264. 
Mimicry,  347,  348. 
Mineral  matter  accumulated  in  the 

leaf,  165. 
Mistletoe,  337. 
Modified  leaves,  121. 
Moisture-plants,  311-313. 
Monadelphous,  202,  *204. 
Monocotyledonous  plants,  34,  233. 
Monocotyledonous  stems,  *83,  *84, 

*85,  86. 
Monocotyledonous  stems,   growth 

of,  in  thickness,  85,  86. 
Monocotyledonous  stems,   rise  of 

water  in,  *110. 
Monocotyledons,  233. 
Moncecious,  200. 
Monotropa,  169. 
Morning-glory,  rate  of  increase  of, 

390,  391. 

Morphology,  1,  33. 
Moss,  study  of,  281-285. 
Mosses,  281-285*. 
Moths,  *361,  362. 


Mould,  black,  study  of,  257,  258, 

259. 
Movement  of  water  in  plants,  107, 

*108,  *109,  *110,  111,  112,  113. 
Movements  of  floral  organs,  *365, 

*366. 
Movements  of  leaves,  *144,  *145, 

*146. 

Movements  toward  light,  148. 
Mucronate,  *131. 
Mulberry,  *226. 
Mullein,    hairs    from    corolla    of, 

*361. 

Multiple  fruits,  *226. 
Multiple  primary  roots,  14. 
Musci,  232. 

Mushroom,  study  of,  264-266*. 
Mutilated  seedlings,  growth  of,  14. 
Mycelium,  257,  *258. 
Mykorhiza,  342. 
Myrsiphyllum,  79,  *81. 
Myxogasteres,  232. 
Myxothallophytes,  232,  233. 

Naked  buds,  121. 

Nasturtium  leaves,  starch  in,  *170. 

Natural  selection,  394,  395. 

Nectar,  356. 

Nectar-glands,  356. 

Nectar-guides,  358. 

Nectaries,  357. 

Negundo,  radial  and  cross-sections 

of  stem  of,  *89. 

Nemalion,  study  of,  253,  254,  *255. 
Netted-veined,  *133. 
Nettle,  stinging  hair  of,  *184. 
Nightshade,  leaf  of,  *349. 
Nitella,  study  of,  247-250. 
Nitrogen,  171,  340. 
Nocturnal  position,  *144,  *145. 
Node,  31,  32,  83. 


406 


FOUNDATIONS   OF   BOTANY 


Nucleus,  178. 

Nucleus  of  root-hair,  *49. 

Nut,  *222,  223. 

Nutrient  substances,  168,  169,  171. 

Nutrition  of  plants,  165-176. 

Oak  leaves,  arrangement  of,  *140. 

Oat,  root-system  of,  48. 

Obovate,  *131. 

Obtuse,  *131. 

Odors  of  flowers,  357. 

Offensive-smelling  plants,  352. 

Oil,  21,  22. 

Oil,  essential,  24. 

Oil,  extraction,  22. 

Oil,  testing  seeds  for,  21,  22. 

Onion,  bulb  of,  77. 

Onion  leaf,  section  of,  *79. 

Onion,  structure  of,  116. 

Onion,  tests  for  food-materials  in, 

116,  117. 
Oogonia,  *251. 
Oosphere,   *249,   *251,  280,  *284, 

285. 

Oospore,  247,  249. 
Opposite,  *65,  *140,  *141,  *142. 
Orbicular,  *131. 
Orchid,  aerial  roots  of  an,  *37. 
Order,  230. 

Organs,  essential,  *197. 
Organs,  vegetative,  30. 
Oscillatoria,  study  of,  239,  240. 
Osmosis,  50-64. 
Osmosis  in  an  egg,  50,  *51. 
Osmosis  in  root-hairs,  53,  54. 
Ovary,  201,  202,  *203,  *205. 
Ovate,  *131. 
Ovoid,  egg-shaped. 
Ovule,  202,  *203. 
Ovule,  spruce,  fertilized,  *303. 
Ovule,  structure  of,  *215. 


Oxalis  leaf,  development  of,  *127. 
Oxidation,  11,  12. 
Oxygen,  11,  12,  166,  167,  168. 
Oxygen-making,  167,  168. 

Palisade-cells,  *151. 

Palmate,  *133. 

Pampas  region,  393. 

Panicle,  *189,  190. 

Panicum,  *381. 

Pansy,  leaf-like  stipules  of,  *135. 

Papilionaceous  corolla,  *199. 

Papillae  on  stigma  of  a  lily,  *214. 

Paraphyses,  251,  *252. 

Parasites,  39,  336-338. 

Parasitic  roots,  39,  *40. 

Parenchyma,  94. 

Parietal  placenta,  203,  *205. 

Parsnip  root,  study  of,  45,  46. 

Pea  seed,  8. 

Pea  seedling,  mutilated,  14. 

Pea  seedling  on  clinostat,  58. 

Peat  bogs,  327. 

Peat  moss,  *327. 

Pedicel,  *186,  187. 

Peduncle,  *186,  187. 

Peg  of  squash  seedling,  27. 

Pepo,  224. 

Perennial,  47,  71. 

Perfect,  198. 

Perianth,  *197. 

Pericarp,  224. 

Perigynous,  204,  *205. 

Perithecia,  263. 

Permanganate  test,  28. 

Petal,  197. 

Petiole,  130,  134. 

Phseophyceae,  232. 

Phanerogams,  231,  233. 

Phanerogams,  classes  of,  233. 

Phosphorus,  165. 


INDEX 


407 


Phycomycetes,  232. 

Physcia,  270-273. 

Physiology,  vegetable,  1. 

Pigeon-wheat  moss,  study  of,  281- 
285. 

Pileus,  *264,  265. 

Pine,  seedling,  *33. 

Pine  wood,  *94. 

Pinnae,  leaflets  of  a  pinnately  com- 
pound leaf,  138. 

Pinnate,  *133. 

Pinnules,  *288. 

Pistil,  *197,  201,  202,  *203. 

Pistil,  parts  of,  *203. 

Pitcher-plant,  *340. 

Pith,  *83,  *87,  *88,  *89. 

Placenta,  203,  *205. 

Plankton,  333. 

Plant  colonies,  310. 

Plant  formations,  310. 

Plant  physiology,  definition  of,  1. 

Plant  societies,  307-323,  *312,*322. 

Plants  of  uneatable  texture,  348. 

Plants,  classes  of,  in  relation  to 
economy  of  water,  311. 

Plants,  destruction  of,  by  animals, 
345. 

Plants,  earliest  appearance  of,  298. 

Plants,  mimicry  by,  347,  348. 

Plasmolysis,  52,  53. 

Pleuroeoccus,  study  of,  244,  245. 

Plumule,  7. 

Pod,  219,  223. 

Poisonous  plants,  352. 

Poisonous  seeds,  24. 

Poisons,  plants  containing,  352. 

Pollarded  trees,  128. 

Pollen,  201,  211,  «212. 

Pollen-carrying  apparatus,  355, 
366. 

Pollen,  discharge  of,  *211. 


Pollen  grains,  *212. 

Pollen     grains,    number    of,    per 

ovule,  216. 
Pollen,  protection  of,  from  visitors, 

360-362. 
Pollen,  protection  of,   from  rain, 

*371,  372. 

Pollen  tubes,  212,  213,  *214. 
Pollination,  353-355. 
Polypetalous,  201. 
Polysepalous,  201. 
Polysiphonia,  255. 
Polytrichum,  281-285. 
Pome,  224. 

Pond-scum,  study  of,  241-244*. 
Potash  in  hay,  165. 
Potato  tuber,  76,  *78,  114-116. 
Prickle,  *349. 
Prickly  leaves,  *349. 
Prickly  pear,  *315. 
Primary  root,  36. 
Primrose,  pollination  in  flowers  of, 

*366,  367. 
Procambium,  *96. 
Prosenchyma,  94,  95. 
Propagation,  by  root,  61. 
Propagation,     means    of,     among 

cryptogams,  373. 
Propagation  of  plants,  373-386*. 
Protection  of  plants  from  animals, 

345-352. 
Protection   of    pollen    from    rain, 

*371,  372. 
Proteids,  22,  23. 
Proteids,  tests  for,  23. 
Prothallium,  287,  *289. 
Protococcus,  *244. 
Protonema,  283. 
Protoplasm,  52,  178. 
Protoplasm,  characteristics  of,  181, 

182. 


408 


FOUNDATIONS   OF  BOTANY 


Protoplasm,   circulation  of,   *184, 

185. 

Protoplasm,  continuity  of,  146. 
Pteridophytes,  232. 
Pteridophytes,   remarks    on,    286, 

295-297. 

Puccinia,  study  of,  259-262*. 
Pulvini,  145,  *146. 

Eace,  230. 
Kaceme,  *186. 
Raspberry,  *374. 
Kay,  medullary,  45. 
Kay-flowers,  188,  *189. 
Receptacle,  199. 
Ked  clover,  leaf  of,  *144. 
Regions  of  vegetation,  324. 
Regular  flowers,  198. 
"  Reindeer  moss,"  274. 
Reproduction  in  algae,  256. 
Reproduction  in  ferns,  287,  *288, 

*289,  291. 
Reproduction  in  flowering  plants, 

212-215*. 
Reproduction  in  fungi,  *258,  *259, 

*260,    *261,    *262,    *265,    *266, 

*268,  *270. 
Reproduction    in    morning-glory, 

390,  391. 

Reproduction  in  mosses,  *284,  285. 
Resin  passage,  *93. 
Respiration,  172,  173. 
Retuse,  *131. 
Rhachis,  287,  *288. 
Rhizoids,  hairs  serving  as  roots  in 

mosses    and    liverworts,    *282, 

*289. 

Rhizopus,  study  of,  257,  258,  259. 
Rhodophyceae,  232. 
Rhubarb  roots,  *47. 
Ring,  annual,  *100,  *101. 


Ringent,  *203. 

Rise  of  water  in  stems,  108-113. 

Rockweed,  study  of,  250-252*. 

Root,  36-61. 

Root,  adaptation  to  work,  59,  60. 

Root-cap,  *42. 

Root-climbers,  *39,  73. 

Root,  dicotyledonous,  section,  *44. 

Root,  elongation  of,  30,  31. 

Root,  exogenous,  *44. 

Root,  fleshy,  45,  46,  *47. 

Root-hair,  31,  *32,  *49,  50. 

Root-pressure,  54,  *55. 

Root-section,  *42,  *44. 

Root-sheath  or  root-pocket,  37. 

Root-system,  47,  48. 

Roots,   absorbing   surface  of,   49, 

50. 
Roots,  absorption  and  temperature, 

55,  56. 

Roots,  adventitious,  36. 
Roots,  aerial,  36,  *37,  *38,  *39. 
Roots,  brace-,  *38. 
Roots,  fascicled,  *41. 
Roots,  fibrous,  *41. 
Roots,  growth  of,  30,  31. 
Roots,  hemlock,  lateral  extension 

of,  *60. 
Roots,   movements  of  young,  56, 

*57,  *58,  59. 
Roots,  parasitic,  39,  *40. 
Roots,  primary,  36. 
Roots,  propagation  by,  61. 
Roots,  selective  action  of,  54. 
Roots,  soil-,  36. 
Roots,  storage  of  nourishment  in, 

46,  *47. 

Roots,  structure  of,  41-46. 
Roots,  water,  37. 
Rootstock,  75,  *76,  *77. 
Rotation  of  protoplasm,  *184,  185. 


INDEX 


409 


Round-leafed  mallow,  stamens  and 

pistils  of,  364. 
Russian  thistle,  *379. 
Russian  thistle,  spread  of,  394. 
Rust,  259. 

Rust,  wheat,  study  of,  259-262*. 
Rye  grass,  76. 

Sage,    pollination    in    flowers    of, 

*365,  *366. 
Sago-palm,  113. 
Salver-shaped,  *202. 
Salvinia,  *302. 
Sap,  descent  of,  *109,  110. 
Sap,  rise  of,  107,  108,  *109. 
Saprophytes,  169,  269. 
Sapwood,  105. 
Scalloped,  *132. 
Schizomycetes,  232. 
Schizophycese,  232,  *238. 
Scirpus,  cross-section  of  stem  of, 

*84. 

Sclerenchyma,  84. 
Scouring-rush,  study  of,  292-295*. 
Seasonal  plants,  311. 
Secondary  growth,  *96,  *97,  *100. 
Secondary  root,  36. 
Secondary  roots,  direction  of,  59. 
Sections,  leaf,  *151,  *154. 
Sections,  root,  *42,  *44. 
Sections,  wood,  *100,  *101,  *102. 
Sedge,  rootstock  of,  *76. 
Seed,  5-24. 
Seed-leaf,  *6,  7. 
Seedlings,  25-35. 

Seedlings,  mutilated  growth  of,  14. 
Seed-plants,  231,  233. 
Seed-plants,  classes  of,  233. 
Seeds,  containing  poisons,  24. 
Seeds,  dispersal  of,  377-386*. 
Selection,  natural,  395. 


Selective  absorption,  53,  54. 

Self-pollination,  353. 

Sepal,  197. 

Separated  flowers,  199,  200,  *201. 

Sequoia,  *66,  71,  *106. 

Series,  plants  form  a,  300. 

Serrate,  *132. 

Sexual  generation,  278. 

Shade  plants,  *321. 

Shoot,  30. 

Shrubs^  69,  70. 

Sieve-cells,  *93,  110. 

Sieve-plate,  *93. 

Sieve-tubes,  *93. 

Silica,  165,  241,  294. 

Simple  leaves,  137. 

Simple  pistil,  202. 

Simple  umbel  of  cherry,  *187. 

Sinuate,  *132. 

Sleep  of  leaves,  *144,  *145. 

Slime-fungi,  232. 

Slime  moulds,  178,  *179,  180,  181, 

*236,  237. 
"  Smilax,"  79,  *81. 
Snowflake,    pollen    tube   of,   with 

generative  cells,  *214. 
Solomon's  seal,  parallel-veined  leaf 

of,  *136. 
Soredia,  271. 
Sori,  261,  287,  *288. 
Spatulate,  *131. 
Species,  229. 
Spermagones,  271. 
Spermatia,  271. 
Spike,  188. 

Spine,  *347,  *348,  *350. 
Spiral  vessel,  *92. 
Spirogyra,  study  of,  241,  242,  *243, 

244. 

Sporangium,  287,  *288. 
Spore,  235,  *236. 


410 


FOUNDATIONS   OF  BOTANY 


Spore-capsules,  281. 

Spore-cases,  *258,  *259. 

Spore-fruits,  *254. 

Spore-plants,  231,  232. 

Spore-plants,  classes  of,  232. 

Spore-sacs,  263,  270,  273. 

Spores  of  slime  moulds,  180. 

Sporophyll,  294. 

Sporophyte,  281,  *282,  284,  285, 
289,  291. 

Spruce,  fertilized  ovule  of,  *303. 

Squash  seed,  5,  6. 

Squash  seed,  section,  *6. 

Squash  seedling,  25-27. 

Stamen,  *197,  201,  202,  *203. 

Stamen,  parts  of,  *203. 

Standard,  *199. 

Starch,  17-20,  *19. 

Starch  disappears  during  germi- 
nation, 21. 

Starch  in  leaves,  169,  *170. 

Starch-making,  rate  of,  170,  171. 

Starch,  testing  seed  for,  18. 

Stem,  30-117. 

Stem,  definition  of,  62. 

Stem,  dicotyledonous,  annual, 
gross  structure  of,  86,  *87. 

Stem,  dicotyledonous,  minute 
structure  of,  86-98*. 

Stem,  early  history  of,  *95,  96. 

Stem,  functions  of  cells  of,  105, 
106,  107. 

Stem,  modifiability  of,  79-82*. 

Stem,  monocotyledonous,  *83,  *84, 
*85,  86. 

Stem,  structure  of,  83-103*. 

Stemless  plants,  *72,  73. 

Stems,  62-118. 

Stems,  climbing,  74,  *75. 

Stems,  storage  of  food  in,  113-115. 

Stems,  twining,  *75. 


Stem-structure,  early  history  of, 
*95,  96. 

Sterigmata,  *266. 

Sterilization,  238. 

Stigma,  201,  *203. 

Stigma,  structure  of,  213-215*. 

Stinging  hair,  *184. 

Stipa,  cross-section  of  rolled  and 
unrolled  leaves  of,  *318. 

Stipe,  *264,  265. 

Stipules,  *135,  136. 

Stolon,  with  tips  rooting,  *374. 

Stomata,  104,*151,  *152,*153,*154. 

Stomata,  operation  of,  158,  159. 

Stone-fruit,  224. 

Storage  of  food  in  the  root,  46,  *47. 

Storage  of  food  in  the  stem,  113- 
117. 

Strawberry,  *226. 

Struggle  for  existence,  387-394. 

Study  of  buttercup  flower,  195,  196. 

Study  of  lemon,  217,  218. 

Study  of  tomato,  217. 

Study  of  trillium  flower,  192,  193. 

Study  of  tulip  flower,  194,  195. 

Style,  201,  *203. 

Sugar,  13,  116,  117,  168,  171,  172. 

Sugar,  formed  during  germination, 
13. 

Sugar-cane,  cross-section  of  a  bun- 
dle from,  *110. 

Sundew,  *341,  *342,  343. 

Sun-plants,  *321. 

Supernumerary  buds,  122,  *123, 
*124. 

Survival  of  the  fittest,  394,  395. 

Swarmspores,  180. 

Sweet  pea,  flowers,  *199. 

Symbiont,  340. 

Symbiosis,  273,  340. 

Symmetrical,  198. 


INDEX 


411 


Taper-pointed,  *131. 

Taproot,  *41. 

Teleutospores,  *262. 

Temperature  and  root-absorption, 
55,  56. 

Temperature,  relation  to  germina- 
tion, 9. 

Tendril,  *138. 

Tendril  climbers,  *74. 

Terminal  bud,  63,  121,  122,  *124, 
•126. 

Terminal  flowers,  186,  *191. 

Tertiary  root,  36. 

Testa,  6. 

Tetraspores,  *255. 

Thallophytes,  232,  235-275. 

Thallophytes,  study  of,  237-273*. 

Thallus,  235,  250. 

Thermostat,  9. 

Thistle,  Russian,  *379,  394. 

Thorns  as  branches,  68,  *69. 

Thyme,  stoma  of,  *153. 

Tickle-grass,  *381. 

"Timber  line,"  *329,  *330. 

Tissue,  94,  95. 

Tomato,  study  of,  217. 

Tracheids,  92,  93,  *94. 

Transition  from  stamens  to  petals, 
*209. 

Transpiration,  156. 

Transpiration,  amount  of,  164, 165. 

Transpiration,  measurement  of, 
159,  *160,  161. 

Transportation  by  water,  380,  381. 

Trees,  69. 

Trees,  age  of,  71. 

Trillium,  study  of  flower  of,  192, 
193. 

Trimorphous  flowers,  367. 

Tropaeolum  leaf ,  *132. 

Tropseoluni  leaves,  starch  in,  *170. 


Tropseolum,  petiole,  coiling  of,*  75. 

Tropical  vegetation,  324,  326. 

Tropophytes,  311,  318,  319. 

Truncate,  *131. 

Trunk,  *66,  *67. 

Tuber,  76,  *78. 

Tubercles  on  clover  roots,  *339. 

Tubular  corolla,  *203. 

Tulip,  study  of  flower  of,  194,  195. 

Tumble-weeds,  378,  *379,  *380. 

Turgescence,  184. 

Turnip,  seedling,  *32. 

Twayblade,    beetle   on  flower  of, 

*359. 

Twigs,  study  of,  62-64. 
Twiners,  74,  *75. 
Twining,  rate  of,  74,  75. 
Types,    order   of    appearance    of, 

298-305. 

Umbel,  *187. 

Umbellet,  190. 

Underground  stems,  75,  *76,  *77, 

*78,  *79. 

Uneatable  plants,  348. 
Union  of  pistils,  202,  203. 
Union  of  stamens,  201,  202. 
Uredospores,  261,  *262. 
Usnia,  *271. 

Vacuole,  contractile,  180. 

Variety,  229,  230. 

Vaucheria,    study    of,   245,  *246, 

247. 

Vegetable  physiology,  1. 
Vegetation,  alpine,  328,  *329,  *330, 

*331. 

Vegetation,  aquatic,  332,  333. 
Vegetation,  arctic,  327,  *328. 
Vegetation,  regions  of,  324. 
Vegetation,  temperate,  325,  326. 


412 


FOUNDATIONS   OF  BOTANY 


Vegetation,  tropical,  324,  325. 
Vegetative  organs,  30. 
Vein,  130,  *133,  *136. 
Veining,  *133,  *136. 
Venation,  *133,  134,  135,  *136. 
Venus  flytrap,  *343,  344. 
Vernation,  125,  *126,  127. 
Vertically  placed  leaves,  146,  *147, 

148. 

Vessel,  *92,  106. 
Volva,  *265. 

Water,  absorption  by  roots,  53-55. 
Water,    amount  transpired,    159- 

165. 
Water,  course   through  leaf,  163, 

164. 

Water,  excretion  of,  172,  173. 
Water,  movement  of,    107,   *108, 

*109,  *110,  111,  112,  113. 
Water,  relation  to  germination,  10. 
Water-lily,     white,     insertion    of 

floral  organs,  *205. 
Water-lily,  white,  transitions  from 

petals  to  stamens  in,  *209. 
Water  roots,  37. 
Weapons  of  plants,  349-351*. 
Wedge-shaped,  *131. 
Weeds,  387-390. 
Weeds,  study  of,  388,  389. 
Wheat-grain,  section  of,  *19. 


Wheat  rust,  study  of,  259-262*. 

Wheel-shaped,  *202. 

Whorled,  *293,  294. 

Willow,  adventitious  buds  of,  128. 

Willow,  arctic,  *328. 

Willow,  flowers  of,  *201. 

Wilting,  111. 

Wind-pollination,  354. 

Windsor  bean  sprouting  over  mer- 
cury, 56,  *57. 

Winged  fruits,  377,  *378. 

Wings,  *199. 

Wood,  coniferous,  structure  of,  92, 
*93,  *94. 

Wood  of  linden,  *100. 

Wood  sections,  *100,  *101,  *102. 

Wood,  structure  of,  *93,  *100, 
*101. 

Wood-cell,  *89,  *91,  *101.  - 

Wood-parenchyma,  94. 

Xanthoria,  *271. 
Xerophytes,  311,  313-317*. 

Yarrow,  head  of,  *189. 
Yeast,  study  of,  266-270,  *268. 
Yucca,  335. 

Zones,  vegetation  of,  324-328. 
Zoospores,  236,  *244. 
Zygospores,  236,  *243,  *259. 


BERGEIST'S    BOTANY 


KEY  AND  FLORA 


PACIFIC  COAST  EDITION 


PREPARED    BY 


ALICE   EASTWOOD 

OF  THE  CALIFORNIA  ACADEMY  OF  SCIENCES,  AUTHOR  OF  THE 
FLORA  IN  THE  ROCKY  MOUNTAIN  EDITION 


GINN  &  COMPANY 

BOSTON  •  NEW  YORK  .  CHICAGO  •  LONDON 


COPYRIGHT,  1897,  1901,  BY 
ALICE  EASTWOOD 


ALL  BIGHTS  RESERVED 
15.2 


GINN  &  COMPANY -CAM- 
BRIDGE •  MASSACHUSETTS 


PREFACE 

THIS  Flora  of  the  Pacific  States  has  been  made  to  enable 
pupils  to  obtain  a  clear  idea  of  the  method  of  classifying 
plants  through  practical  experience  in  identifying  the  most 
common  genera  and  species  of  the  coast.  It  is  to  serve  as  a 
guide  in  understanding  the  characteristics  and  relationships 
of  large  and  important  orders  and  genera,  and,  to  some 
extent,  in  identifying  species. 

The  species  included  have  been  those  most  widely  dis- 
tributed or  those  most  abundant  near  large  centers  of  popula- 
tion, so  that  sufficient  material  might  easily  be  obtained  for 
class  study.  Species  not  clearly  and  easily  defined  have  been 
omitted  even  when  abundant,  so  as  to  render  the  possibility 
of  error  as  little  as  possible.  Where  a  difference  of  opinion 
exists  among  botanists  in  regard  to  generic  names,  both  have 
generally  been  given,  one  in  parentheses. 

Teachers  will  find,  in  whatever  part  of  the  Pacific  States 
they  may  be,  that  they  can  collect  a  sufficient  number  of  the 
plants  here  included  to  afford  their  pupils  all  the  drill  neces- 
sary. It  is  advised  that  the  teachers  furnish  the  plants  for 
class  study,  being  careful  to  select  only  from  those  here 
included  rather  than  to  allow  the  pupils  themselves  to  select 
at  random  from  the  flora  of  the  neighborhood ;  otherwise,  the 
pupil  is  likely  to  become  discouraged  by  failure  in  identifying 
plants  not  described  in  the  book. 


2  PREFACE 

Teachers  who  are  in  doubt  about  any  plants  are  earnestly 
requested  to  send  specimens  to  the  Academy  of  Sciences,  San 
Francisco,  where  they  will  be  compared  with  herbarium  speci- 
mens and  identified.  The  specimens  should  have  both  flower 
and  fruit  when  possible,  and  in  the  case  of  herbs  the  entire 
plant  should  be  sent,  root  and  all.  % 

It  requires  quite  a  library  of  botanical  books  to  identify 
Pacific  Coast  species,  since  there  is  no  book  published  that 
contains  even  all  the  known  species,  and  there  are  many 
species  still  undiscovered.  It  is  neither  possible  nor  desirable 
to  attempt  to  include  all  in  a  school  flora.  The  chief  books 
needed  for  a  more  complete  study  are  the  two  large  and 
expensive  volumes  of  the  State  Geological  Survey ;  the  fol- 
lowing botanical  works  of  Prof.  E.  L.  Greene  :  Pittonia,  Flora 
Franciscana,  and  The  Botany  of  the  Bay  Region  ;  Western 
Cone-bearers,  by  J.  G.  Lemmon ;  and,  for  Composites  and 
Gamopetalce,  Gray's  Synoptical  Flora. 

The  plan  of  arrangement  in  preparing  this  Flora  has  been 
that  of  Professor  Bergen's  Key  and  Flora  to  the  Spring- 
blooming  Plants  of  the  Northern  and  Middle  States,  which 
replaces  this  in  the  Eastern  edition  of  his  book.  It  seemed 
that  a  plan  which  he  had  tried  and  found  successful  was 
better  to  adopt  than  one  that  was  new  and  untried.  When- 
ever possible,  his  descriptions  have  been  used,  the  aim 
throughout  having  been  to  follow  as  he  led. 

The  botany  of  the  Geological  Survey,  Professor  Greene's 
botanical  works,  and  Dr.  Behr's  Botany  of  the  Vicinity  of  San 
Francisco  have  all  been  used  in  compiling  the  descriptions 
and  making  the  Key. 


PKEFACE  3 

The  figures  referred  to  are  to  be  found  in  the  text  of  this 
Key,  unless  the  reference  is  preceded  by/,  or  e.  The  former 
refers  to  Bergen's  Foundations  of  Botany,  the  latter  to  his 
Elements  of  Botany. 

The  pronunciation  is  indicated  by  accent  marks  and  the 
division  of  the  accented  syllable.  A  vowel  ending  this 
syllable  has  a  long  sound;  but  when  the  accented  syllable 
ends  in  a  consonant,  the  vowel  has  a  short  sound.  It 
matters  little  whether  the  English  or  Continental  sounds 
for  the  vowels  are  used ;  the  former  are  more  generally 
authorized,  though  the  latter  are  becoming  more  and  more 
prevalent. 

In  this  revised  edition  I  am  indebted  to  Prof.  C.  V.  Piper, 
of  the  Agricultural  College,  at  Pullman,  Washington,  for 
additions  to  the  Flora  from  Washington  and  Oregon,  and 
to  Mr.  Louis  A.  Greata,  of  Los  Angeles,  for  additions  from 
the  country  adjacent  to  Los  Angeles. 

ALICE  EASTWOOD 

ACADEMY  OF  SCIENCES 

SAN  FRANCISCO 


KEY  TO  SOME   FAMILIES    OF   PHANEROGAMS 


GYMNOSPERMS.    Ovules  not  enclosed  in  an  ovary. 

Trees  or  shrubs,  usually  with  needle-shaped  or  scale-like  evergreen  leaves  and 
monoecious  or  dioecious  flowers  in  catkins,  the  pistillate  ones  usually  ripening 
into  cones (Coniferae),  Fine  Family,  p.  13 

ANGIOSPERMS.    Ovules  in  an  ovary. 

MONOCOTYLEDONS.     Flowers  generally  on  plan  of  3,  never  of  5 ;  leaves 
usually  parallel-veined. 

GLUMACEOUS    DIVISION.       Flowers  rudimentary,  enclosed  in  husk-like 

bracts. 
Bracts  for  each  flower  2 ;  stems  jointed,  hollow,  cylindrical  or  nearly 

so (Graminese),  Grass  Family,  p.  21 

Bracts  for  each  flower  1;  stems  not  jointed,  solid,  triangular 

(Cyperaceae),  Sedge  Family,  p.  22 

PETALOIDEOUS  DIVISION.    Flowers  havinga  true  perianth  ;  not  on  a  spadix. 
Ovary  free  from  the  perianth,  stamens  6 

(Liliaceae),  Lily  Family,  p.  23 
Ovary  adnate  to  the  perianth. 
Stamens  6       .     (Amaryllidaceae),  Century  Plant  Family,  p.  36 

Stamens  3 (Iridaceae),  Iris  Family,  p.  37 

Stamens  1  or  (rarely)  2    .     .     (Orchidacese),  Orchis  Family,  p.  39 

DICOTYLEDONS.     Flowers  generally  on  the  plan  of  4  or  5.    In  woody 

plants  the  woody  fiber  forms  concentric  rings. 

DIVISION  I.     APETAL^E.     With  but  one  set  of  floral  envelopes  or  none. 
Flowers  in  catkins.     Trees  or  shrubs. 

Dioecious,  1  flower  to  each  scale  of  the  catkin ;  fruit  a  many-seeded  pod, 
each  seed  furnished  with  a  tuft  of  cotton 

(Salicacese),  Willow  Family,  p.  40 

Monoecious  ;  sterile  catkins  drooping  ;  fertile,  erect,  cone-like,  with  1  or 
2  flowers  under  each  stiff,  shield-shaped  scale 

(Betulacese),  Alder  Family,  p.  42 
5 


KEY  AND  FLOBA 

Monoecious,  androgynous ;  catkins  short,  erect,  with  1  flower  under 
each  scale  of  the  fertile  catkin  ;  fruit  a  round  nutlet 

(Myricacese),  Wax-myrtle  Family,  p.  40 

Monoecious,  sterile  flowers  only  in  catkins  ;  fruit  a  nut  in  a  cup  or  bur, 
or  a  leaf -like  cylindrical  sheath 

(Cupuliferae),  Oak  Family,  p.  44 

Dioecious,  sterile  flowers  with  calyx  4-parted,  stamens  4 ;  fertile  flowers 
with  calyx  2-lobed  or  wanting,  ovary  1-celled,  2-ovuled,  styles  2 ; 
fruit  a  berry  (Garry acese),  Silk-tassel  Bush  Family,  p.  120 

Flowers  not  in  catkins. 
Ovary  inferior, 

6-celled,  perianth   regular  and  3-lobed  or  irregular,  stamens   6-12 
(Aristolochiacese),  Dutchman's  Pipe  Family,  p.  46 

l-celled,  sunk  in  the  axis  of  the  conical  spike,  which  has  numerous 
flowers,  and  a  persistent  petal-like  involucre ;  flowers  naked,  of 
6-8  stamens  and  3-6  pistils,  each  subtended  by  a  white  bract. 
Aromatic  herbs  of  wet  alkaline  places 

(Houttuynia),  Yerba  Mansa,  p.  40 

Ovary  superior, 

3-celled,  3-ovuled,  stigmas  3-6.  Monoecious  or  dioecious.  Staminate 
flowers  with  1  to  many  stamens.  Plants  with  milky  juice 

(Euphorbiacese),  Spurge  Family,  p.  99 

l-celled,  forming  a  3-sided  akene,  stamens  9,  perianth  of  6  divisions 
usually  colored  like  a  corolla 

(Polygonacese),  Buckwheat  Family,  p.  47 

l-celled,  forming  a  flat  akene  with  embryo  coiled,  stamens  5  opposite 
the  divisions  of  the  green  perianth  ;  plants  often  fleshy  and  covered 
with  scurf  .  .  (Chenopodiacese),  Pigweed  Family,  p.  49 

Similar  to  Chenopodiacese,  but  the  divisions  of  the  perianth  are 
papery  and  persistent  with  similar  bracts 

(Amarantaceae),  Amaranth  Family,  p.  51 

l-celled,  1-seeded,  calyx  corolla-like,  monosepalous,  the  persistent 
herbaceous  base  hardening  around  the  akene,  style  1 ;  flowers  in 
calyx-like  involucres 

(Nyctaginacese),  Four-o'clock  Family,  p.  51 

Stamens  9  in  3  rows,  anthers  4-celled,  opening  by  uplifted  valves  ; 
sepals  6,  petaloid,  pistil  simple ;  flowers  in  umbels ;  trees  with 
aromatic  foliage  .  .  .  (Lauraceae),  Laurel  Family,  p.  63 

DIVISION  II.      POLYPETALJE.      Petals  distinct  (in  some  genera  wanting). 
Stamens  hypogynous  (on  the  receptacle  below  the  superior  ovary). 


PHANEROGAMS 


Stamens  Numerous 

Separate,  and  the  other  floral  organs  distinct,  petals  sometimes  want- 
ing, flowers  with  the  sepals  5  or  irregular 

(Ranunculacese),  Buttercup  Family,  p.  58 

Separate,  flowers  regular,  sepals  (generally  2)  half  as  many  as  the 
petals  and  falling  as  the  petals  expand 

(Papaveracese),  Poppy  Family,  p.  64 

Monadelphous,  attached  to  the  bases  of  the  petals. 
Anthers  1-celled,  kidney-shaped 

(Malvaceae),  Mallow  Family,  p.  105 

Anthers  2-celled,  petals  wanting,  sepals  petal-like 

(Fremontia),  p.  107 

United  into  3-5  bunches,  sepals  and  petals  5,  leaves  opposite,  punctate 
(Hypericacese),  St.  John's-wort  Family,  p.  107 

About  20,  sepals  5  (2  scale-like),  petals  5,  soon  falling 

(Cistaceae),  Rockrose  Family,  p.  108 

Stamens  10  or  less 

10  (rarely  fewer),  petals  5  (sometimes  wanting),  capsule  splitting  into 
twice  as  many  valves  as  styles.  Seeds  on  axillary  placenta 

(Caryophyllaceae),  Pink  Family,  p.  55 

10  or  5,  sepals  and  petals  5,  carpels  5  on  a  spike-like  axis,  distinct  at 
base  but  cohering  by  their  stigmas  and  separating  from  the  axis  at 
the  base  first,  1-seeded (Geraniacese),  p.  95 

10,  sepals  and  petals  5,  carpels  distinct,  1-seeded,  globose,  at  the  base  of 
a  common  style ;  juice  pungent  .  .  .  (Limnanthes),  p.  97 

10,  sepals  and  petals  5,  carpels  united  into  a  5-celled  ovary  with  5  styles  ; 
leaves  compound  with  3  leaflets ;  juice  acid  .  .  (Oxalis),  p.  97 

10  or  5,  equal  to  or  double  the  number  of  petals ;  herbs  with  fleshy 
leaves  ....  (Crassulacese),  Stonecrop  Family,  p.  74 

6  or  9,  anthers  2-celled,  opening  by  uplifted  valves  (/.  Fig.  160,  II ; 
e.  Fig.  138,  II) ;  bracts,  sepals,  petals,  and  stamens  opposite  each 
other;  pistil  simple  (Berberidaceae),  Barberry  Family,  p.  62 

6  (4  long  and  2  short),  petals  and  sepals  4  (petals  sometimes  wanting) ; 
fruit  2-celled  with  a  papery  partition,  or  sometimes  1-celled  and 
indehiscent ;  herbs  with  pungent  juice 

(Cruciferse),  Mustard  Family,  p.  67 

6,  or  sometimes  more,  nearly  equal,  sepals  and  petals  4  ;  pod  1-celled,  on 
a  long  slender  stalk  (Capparidacese),  Caper  Family,  p.  73 


KEY   AND   FLORA 

6,  united  by  the  filaments  to  form  2  equal  sets  ;  flowers  irregular 

(Fumariacese),  Bleeding  Heart  Family,  p.  66 

5,  sometimes  united  over  the  pistil ;  petals  5,  one  of  them  with  a  spur 

(Violacese),  Violet  Family,  p.  109 

1  to  many,  sepals  2-8,  petals  5-16,  styles  3-8-cleft,  ovary  1-celled  with 

placenta  axillary;    plants  with  fleshy  leaves  and  mostly  showy 
flowers  that  open  only  in  bright  sunshine 

(Portulacacese),  Portulaca  Family,  p.  52 

Stamens  4-7,  petals  4-5  with  long  claws,  ovary  1-celled,  with  as  many 
parietal  placentae  as  divisions  of  the  style 

(Frankeniacese),  Yerba  Reuma  Family,  p.  108 

6-8,  the  filaments  united  into  a  split  sheath ;  flowers  irregular,  super- 
ficially resembling  the  Papilionacese,  sepals  5,  petals  2;  pod 
2-celled,  flattened  contrary  to  the  partition 

(Polygalaceae),  Polygala  Family,  p.  98 

5,  monadelphous  at  base,  petals  soon  falling,  capsule  splitting  into 
twice  as  many  divisions  as  stigmas 

(Linace86),.Flax  Family,  p.  98 

2  (rarely  3  or  4),  petals  4,  2,  or  wanting,  calyx  4-toothed ;  fruit  winged 

from  the  summit,  1-seeded ;  polygamous  or  dioecious  trees  or  shrubs 
with  opposite  compound  leaves      .     .    (Fraxinus),  Ash,  p.  128 

Ovary  superior  or  nearly  so. 

Stamens  distinctly  on  the  calyx  or  on  a  disk  simulating 
a  calyx  tube 

Numerous ;  ovary  simple  or  compound,  free  from  or  partly  united  to 

the  disk  ;  leaves  alternate,  with  stipules  that  sometimes  fall  early  ; 

seeds  without  endosperm  (Rosacese),  Rose  Family,  p.  80 

Stamens  indefinite,  petals  merging  into  the  sepals,  carpels  numerous, 

becoming  akenes  within  a  hollow  disk;    aromatic  shrubs,  having 

opposite  leaves  and  no  stipules 

(Calycanthacese),  Sweet  Shrub  Family,  p.  80 

Variable  in  number  (5,  10,  20),  carpels  2-5,  completely  or  partially 
united  to  the  calyx,  styles  distinct ;  leaves  without  stipules  ;  seed 
with  endosperm  (Saxifragacese),  Saxifrage  Family,  p.  75 

10,  distinct,  monadelphous  or  diadelphous ;  flowers  papilionaceous ; 
fruit  a  legume  .  .  .  (Papilionacese),  Pea  Family,  p.  89 

Numerous,  distinct;  flowers  regular  of  4  or  5  sepals  and  petals  ;  fruit 
a  legume (Mimosese),  Acacia  Family,  p.  95 

5  or  fewer,  petals  minute  and  scale-like  (or  none) ;  fruit  a  loosely 
covered  1-seeded  indehiscent  pod  enclosed  in  the  persistent  calyx  ; 

stipules  papery         (Illecebracese),  Sand  Mat  Family,  p.  57 


PHANEROGAMS 


Stamens  on  a  disk,  not  simulating  a  calyx  tube 

Inserted  on  the  inner  margin  of  the  disk,  as  many  or  twice  as  many  as 
the  petals  and  alternate  with  them  (usually  5);  ovary  1-celled, 
1-ovuled  ;  fruit  a  berry 

(Anacardiacese),  Poison  Oak  Family,  p.  101 

Inserted  on  the  outer  margin  of  the  disk,  as  many  as  the  petals  and 
opposite  them  (petals  sometimes  'wanting) ;  style  or  stigma  2- 
4-lobed ;  fruit  a  berry  or  dry  pod  with  2-4  hard  seeds 

(Rhamnacese),  Buckthorn  Family,  p.  103 

5-8,  corolla  irregular  with  4  or  5  unequal  petals  ;  ovary  3-celled,  ovules 
6,  only  1  maturing  ....  (^Esculus),  Buckeye,  p.  102 

3-12  (usually  8) ;  flowers  perfect  with  petals,  or  dioecious  and  apetalous  ; 
fruit  of  2  parts,  each  winged  (/.  Fig.  169,  II ;  e.  Fig.  172,  II) 

(Acer),  Maple,  p.  102 

Ovary  distinctly  inferior. 

Stamens  perigynous  (on  the  calyx) 

Stamens  4-8,  sepals  and  petals  4 ;  ovary  4-celled 

(Onagracese),  Evening  Primrose  Family,  p.  Ill 

Stamens  numerous,  usually  some  petaloid,  petals  and  sepals  5 ;  herbage 
adhesive  with  barbed  hairs 

(Loasaceae),  Blazing  Star  Family,  p.  115 

Stamens,  petals,  and  sepals  numerous;  fruit  fleshy,  1-celled;  spiny, 
leafless  plants  .  .  .  (Cactacese),  Cactus  Family,  p.  115 

Stamens  and  petals  numerous,  sepals  5,  capsules  3-5-celled  ;  leaves  and 
stems  fleshy  .  .  (Ficoideae),  Fig  Marigold  Family,  p.  116 

Stamens  numerous  ;  ovary  3-5-celled,  opening  at  the  top  ;  calyx  falling 
off  like  a  lid,  setting  free  the  stamens  and  producing  a  tassel-like 
blossom (Eucalyptus),  Gum  Tree,  p.  110 

Stamens  eplgynous  (on  the  ovary) 

Stamens,  petals,  and  sepals  5  (the  last  very  small),  styles  2  ;  fruit  a  pair 
of  seed-like  carpels ;  flowers  small  in  umbels ;  leaves  alternate, 
compound  .  .  .  (Umbelliferse),  Parsley  Family,  p.  117 

Similar  to  Umbelliferae,  except  the  styles  and  carpels  4  or  5 ;  fruit  a 
berry,  and  umbels  panicled 

(Araliacese),  Ginseng  Family,  p.  116 

Stamens,  sepals,  and  petals  4  ;  fruit  a  1-seeded  berry  ;  flowers  in  cymes 
or  heads  ;  leaves  simple,  opposite 

(Cornacese),  Dogwood  Family,  p.  119 


10  KEY  AND  FLOKA 

"""•  DIVISION  III.     GAMOPETAL^E.     Petals  united  into  a  cup  or  tube. 

~  Vvary  free  from  the  calyx  (superior). 
— *-  Corolla  regular. 

~— -Ovary  deeply  4-lobed,  in  fruit  forming  4  nutlets 

(Borraginacese),  Borage  Family,  p.  137 
Ovary  2-celled,  ovules  numerous  ;  fruit  often  a  berry 

(Solanacese),  Nightshade  Family,  p.  145 
Ovary  2-celled  (generally  4-ovuled) ;  twining  plants 

(Convolvulacese),  Morning-glory  Family,  p.  132 
Ovary  1-celled  or  imperfectly  2-celled,  styles  2-cleft  or  entire 

(Hydrophyllacese),  Baby-eyes  Family,  p.  133 
Ovary  3-celled  with  axillary  placenta,  style  3-lobed 

(Poleinoniacese).,  Phlox  Family,  p.  130 
Ovary  1-celled  with  2  parietal  placentae,  style  1,  stigmas  2 

(Gentianacese),  Gentian  Family,  p.  128 

Ovary  cells  as  many  as  petals,  style  1,  anthers  2-celled,  opening  by 

holes  at  the  top   .     .     (Ericaceae),  Heather  Family,  p.  120 

Ovary  1-celled  with  axillary  placenta,  stamens  opposite  the  petals 

(Primulaceae),  Primrose  Family,  p.  125 

Ovary  5-angled,  1-celled,  1-seeded,  styles  5 

(Plumbaginacese),  Sea  Pink  Family,  p.  127 

Ovary  2-celled  (sometimes  3-4-celled)  with  1  seed  in  each  cell  (some- 
times more  in  Plantago  major) 

(Plantaginaeeee),  Plantain  Family,  p.  153 

Ovaries  2,  distinct,  with  a  stigma  common  to  both  and  united  with  a 
crown-like  column  of  stamens ;  flowers  in  umbels ;  seeds  with  a 
tuft  of  silky  hairs  ;  plants  with  milky  juice 
(Asclepiadacese),  Silkweed  or  Milkweed  Family,  p.  129 

Similar  to  Asclepiadacese,  except  that  the  stamens  are  distinct  and 

free  from  the  stigma,  but  the  anthers  are  disposed  to  cohere  with  it 

(Apocynacese),  Dogbane  Family,  p.  130 

Corolla  irregular.      Fertile  stamens  fewer  than  the  divisions  of  the 

corolla. 

Ovary  deeply  4-lobed,  becoming  4  nutlets ;  corolla  2-lipped ;  aromatic 

herbs  or  shrubs      .     .     .     (Labiatae),  Mint  Family,  p.  139 

Ovary  2-celled,  seeds  many  on  a  central  placenta,  style  and  stigma  1 

(Scrophulariaceae),  Figwort  Family,  p.  146 

Ovary  2-celled  with  2  or  more  parietal  placentas,  seeds  many  ;  root- 
parasites  without  leaves  or  green  color 

(Orobanchacese),  Broom  Rape  Family,  p.  153 


PHANEROGAMS  11 

Ovary  adnate  to  the  calyx  (inferior). 

Ovary  with  as  many  cells  as  petals,  anthers  2-celled,  opening  by  holes 
at  the  top  (/.  Fig.  160,  in ;  e.  Fig.  138,  in) ;  fruit  a  berry 

(Vaccinium),  Huckleberry,  p.  120 

Ovary  2-5-celled (sometimes  becoming  1-celled);  fruit  a  berry;  leaves 
opposite,  without  stipules 

(Caprifoliacese),  Honeysuckle  Family,  p.  156 

Ovary  2-5-celled;  leaves  opposite  with  stipules,  or  whorled  and 
without  stipules  .  .  (Rubiacese),  Madder  Family,  p.  154' 

Ovary  1-3-celled ;  flowers  monoecious  or  dioecious ;  trailing  or 
climbing  tendril-bearing  herbs ;  fruit  fleshy,  indehiscent 

(Cucurbitaceae),  Gourd  Family,  p.  158 

Ovary  2-5-celled,  with  axillary  placenta,  style  2-5-cleft 

(Campanulacese),  Harebell  Family,  p.  159 

Ovary  2-celled  with  axillary  placenta,  or  1-celled  with  parietal 
placentae ;  stamens  united  by  both  filaments  and  anthers 

(Lobeliaceae),  Lobelia  Family,  p.  160 

Ovary  3-celled,  2  cells  empty,  fruit  1-seeded ;   stamens  3,  corolla 

tubular,  slightly  irregular,  border  of  the  calyx  plumose  or  wanting 

(Valerianacese),  Valerian  Family,  p.  158 

Ovary  1-celled,  becoming  an  akene,  stamens  united  by  their  anthers 
(/.  Fig.  153 ;  e.  Fig.  131) ;  flowers  many,  combined  in  heads  and 
appearing  like  a  single  flower  (/.  Fig.  133 ;  e.  Fig.  110) 

(Composite),  Sunflower  Family,  p.  161 


CLASS  L  —  GYM'NOSPERMS 

Plants  destitute  of  a  closed  ovary,  style,  or  stigma  ;  ovules 
generally  borne  naked  on  a  carpellary  scale,  which  forms  part 
of  a  cone.  Cotyledons  often  several. 

CONIF'ERJE.     PINE  FAMILY 

Trees  or  shrubs  with  wood  of  peculiar  structure,  destitute 
of  ducts,  with  resinous  and  aromatic  juice.  Leaves  generally 
evergreen  and  needle-shaped  or  scale-shaped.  Flowers  desti- 
tute of  floral  envelopes,  monoecious  or  dioecious.  Male  flowers 
consisting  of  stamens  arranged  in  a  spike,  and  resembling  a 
catkin,  with  pollen  sacs  at  the  base  of  scales,  subtended  by  a 
cluster  of  bracts  like  an  involucre.  Female  flowers  consisting 
of  naked  ovules  at  the  base  of  scales  arranged  in  a  spike  with 
a  cluster  of  bracts  below,  in  fruit  forming  a  cone  with  the 
seeds  under  the  scales  or  becoming  a  one-  to  few-seeded  berry. 

I.    JUNIP'ERUS,  Juniper,  Cedar 

Flowers  dioecious,  axillary  or  terminal.  Staminate  clusters 
numerous,  with  scales  whorled  or  opposite,  on  a  central  axis, 
and.  2-6  anther  cells  to  each  scale.  Pistillate  clusters  of 
3-6  fleshy  scales,  each  bearing  1-2  erect  ovules.  Fruit  a 
berry.  Seeds  bony.  Shrubs  or  low  trees,  usually  branching 
irregularly,  with  aromatic  wood  and  thin,  shreddy  bark. 
Leaves  either  triangular,  scale-like,  folding  over  each  other, 
or  linear,  rigid,  pointed,  and  free  from  each  other. 

II.    CUPRES'SUS,  Cypress 

Monoecious.  Staminate  clusters  small,  very  numerous,  and 
at  the  tips  of  tiny  branchlets  ;  pollen  sacs  3-5  at  the  base 
of  each  scale.  Fertile  clusters  erect  on  short  lateral  branchlets, 

13 


14  KEY  AND   FLORA 

forming,  when  ripe,  roundish  or  oblong  woody  cones,  con- 
sisting of  6-10  very  thick,  shield-shaped  scales,  fitting  closely 
together  ;  cones  maturing  in  two  years  in  all  except  the  last ; 
ovules  numerous,  in  several  rows  at  the  base  of  the  scales, 
forming  acutely  angled  seeds.  Leaves  evergreen,  scale- 
shaped,  imbricated.  When  the  tree  is  allowed  to  grow 
naturally,  it  is  pyramidal,  or  roundish,  with  rather  loose, 
straggling  branches  and  pointed  or  rounded  at  the  top.  In 
bloom  in  winter  or  early  spring. 

a.  C.   macrocarpa    Hartweg.      MONTEREY   CYPRESS.     This   has 
dense    foliage  and  oblong  cones  clustered  on   short   stems.      It  is 
extensively  cultivated  throughout  California  for  wind  breaks  and 
hedges;   also  trimmed  into   the   most  fantastic  shapes,  which  are 
supposed  to  be  ornamental. 

b.  C.  Govenia'na  Gordon.     MOUNTAIN  CYPRESS.     This  is  a  more 
loosely  branched  and  smaller  tree,  with  the  upper  branches  slender 
and  drooping.      The  cones  are  an  inch  or  less  long,  and  are  globose, 
rarely  oblong.     This,  too,  is  cultivated.     In  its  native  state  it  grows 
throughout  the  Coast  Mountains. 

c.  C.  Macnabia'na  Murr.    This  is  a  small  tree  with  fine  foliage  very 
fragrant,  sprinkled  all  over  with  white  glands,  so  that  the  tree  is  pale 
green.     The  cones  are  small,  with  horn-like  projections  on  the  scales. 
This  also  is  cultivated,  but  rarely.     It  is  a  native  of  the  mountains 
of  Lake  County. 

d.  C.  Lawsonia'na  Murr  (Chamaecy'paris).     PORT  ORFORD  CEDAR. 
This  differs  from  the  other  species  of  Cupressus  in  having  flattened, 
2-ranked  branches,  and  the  cones  ripening  in  one  year.     Cones  very 
small,  £  of  an  inch  in  diameter,  globose,  with  8  or  10  flat  scales  which 
are  bluish  green  when  young.     Seeds  2-4  to  each  scale,  somewhat 
winged.      This  is  a  tall,  symmetrical  tree  with  slender  branches, 
often  drooping.     It  is  frequently  cultivated  and  is  a  very  valuable 
timber  tree.    The  wood  is  very  fragrant  and  is  used  in  making  chests 
and  cupboards  where  it  is  desirable  to  keep  out  insects.     It  is  also 
known  as  Oregon  Cedar  and  Ginger  Pine.     It  is  found  chiefly  in  the 
Coast  Mountains  of  Oregon. 


HI.    THU'YA,  Arbor-vitae 

Monoecious.  Staminate  flowers  numerous,  very  small,  with 
3  or  4  pollen  sacs  at  the  base  of  the  4-6  pointed  scales. 
Fertile  clusters  at  the  ends  of  branchlets.  Cones  very  small, 
%  inch  long,  soon  reflexed,  ripening  in  one  year,  with  8-12  erect 


GYMNOSPERMS  15 

scales  in  pairs,  having  a  pair  of  winged  seeds  under  all  except 
the  top  and  bottom  pair.  These  are  tall,  symmetrical  trees,  with 
horizontally  flattened  branches  and  scale-shaped,  evergreen 
leaves  adnate  and  decurrent  in  4  rows,  with  the  tips  free. 

T.  gigante'a  Nutt.  This  is  a  very  tall  tree  found  in  the  Coast 
Mountains  of  Oregon,  in  Washington,  northern  Idaho,  and  British 
Columbia.  The  cones  are  densely  clustered  at  the  ends  of  the  droop- 
ing branchlets,  and  the  foliage  is  a  bright,  shining  green.  The  bark 
is  thin  and  fibrous,  the  wood  soft  but  durable. 


IV.    LIBOCE'DRUS,  Incense  Cedar 

Similar  to  Thuya,  but  with  12  or  more  scales  on  the  stami- 
nate  cluster  and  with  the  cones  not  reflexed.  These  consist  of 
4-6  thick  scales  in  pairs,  the  two  largest  only  bearing  seeds. 
Seeds  with  unequal  wings. 

L.  decur'rens  Torrey.  This  becomes  a  large  tree  in  the  Sierra 
Nevada  Mountains  and  has  a  trunk  resembling  that  of  the  giant 
Sequoia.  It  is  also  found  on  almost  all  the  higher  hills  of  the 
Coast  Mountains. 

V.    SEQUOI'A,  Redwood 

Monoacious.  Staminate  flowers  small,  very  numerous  near 
the  ends  of  young  shoots,  with  3-5  pollen  sacs  under  each 
scale.  Fertile  flowers  at  the  ends  of  branchlets,  consisting  of 
several  scales  with  long-pointed  tips  which  become  bristles  on 
the  shield-shaped  scales  of  the  cone.  Each  scale  is  diamond- 
shaped  with  lines  running  to  the  center,  giving  the  cone  a 
quilted  appearance.  The  Sequoias  are  the  largest  trees  on 
earth.  Their  leaves  are  flattened  or  triangular  scale-shaped ; 
the  bark  very  thick,  fibrous,  and  spongy ;  the  wood  red  and 
soft,  easily  split  longitudinally,  and  the  bark  also  cleaving 
longitudinally.  Both  species  are  cultivated  in  different  parts 
of  California. 

a.  S.  semper'virens  Endl.  REDWOOD.  Cones  small,  oblong,  of 
about  20  scales,  maturing  in  one  season ;  lower  leaves  flat,  2-ranked ; 
upper  leaves,  on  tall  trees,  scale-shaped.  This  forms  immense  forests 
in  northern  California  and  extends,  along  the  coast,  from  southern 
Oregon  to  Point  Gorda  in  Monterey  County.  The  specific  name 


16  KEY  AND  FLORA 

arises  from  its  tenacity  of  life.     It  sends  up  new  trees  in  a  circle 
around  where  a  tree  has  been  cut  down.     In  bloom  in  winter. 

b.  S.  gigante'a  Decaisne.  MAMMOTH  SEQUOIA,  BIG  TREE. 
Upper  and  lower  leaves  alike,  scale-shaped,  with  long-pointed  tips  : 
cones  about  2  in.  long  of  25-30  scales,  requiring  two  seasons  to 
ripen.  This  is  found  in  groves  in  moist,  protected  valleys  in  the 
higher  Sierras,  from  Placer  County  through  Tulare  County. 

VI.    A'BIES,  Fir 

Tall  trees  tapering  from  a  rather  broad  base  to  a  pointed 
top,  with  horizontal  branches  and  brittle  wood  that  soon 
decays.  Leaves  apparently  in  2  ranks,  generally  erect, 
twisted  at  base.  Cones  erect,  near  the  top  of  the  tree,  the  scales 
and  seeds  falling  away  from  the  axes,  which  remain  like 
candles  on  a  Christmas  tree.  The  cones  are  therefore  never 
found  under  the  trees,  only  the  fallen  scales. 

a.  A.  con'color  Lindl.     WHITE  FIR.     Large  trees  with  old  bark 
rough,  gray,  and  furrowed.     Leaves  pale  green,  obtuse.     Cones  3-5 
in.    long,    green    or   purple   when    ripe.     This   is   the    common   fir 
of  middle  elevations  in   the   Sierra   Nevada   Mountains.      It   also 
extends  into  Oregon. 

b.  A.  gran'dis  Lindl.     Tall  and  large  trees  with  smooth,  brownish 
bark.     Leaves  dark  green  and  glossy  on  the  upper  surface,  with  2 
white  lines  on  the  lower,  obtuse  or  notched  at  apex.     Cones  2-4  in. 
long.     This  is  probably  the  tallest  fir  in  the  world.     It  is  found 
near  the  coast  from  northern  California  to  British  Columbia  and  is 
one  of  the  most  important  sources  of  lumber. 


VII.    PI'CEA,  Spruce 

Tall  trees,  shaped  as  the  firs,  and  with  soft  but  strong 
wood.  Leaves  sessile,  spirally  arranged,  falling  from  the 
branchlets  as  soon  as  dry  and  leaving  the  steins  covered  with 
numerous  tiny  projections,  sometimes  appearing  in  2  ranks. 
Cones  drooping,  growing  on  the  upper  branches,  falling  to  the 
ground  when  ripe  and  always  to  be  found  under  the  bearing  trees 
with  the  scales  spirally  arranged  on  the  axes. 

a.  P.  Sitchen'sis  Carr.  TIDELAND  SPRUCE.  Very  tall  and  large 
trees  with  thin,  scaly,  brownish  red  bark.  Leaves  slender,  sessile, 
with  short  points  at  the  apex.  Cones  1^-3  in.  long,  yellowish. 


GYMNOSPERMS  17 

This  is  one  of  the  most  important  trees  of  the  northern  Pacific 
coast  and  is  probably  the  largest  spruce  in  the  world.  It  extends 
from  northern  California  to  Alaska. 

&.  P.  Engelman'ni  Engelm.  ENGELMANN  SPRUCE,  WHITE  SPRUCE. 
Bark  light  cinnamon-red,  broken  into  thin  loose  scales.  Young- 
trees  of  pyramidal  outline  ;  old  trees  in  forests  with  long  straight 
trunks  and  pyramidal  at  top.  Leaves  stiff,  ending  in  a  sharp  tip. 
Branchlets  pubescent.  Cones  cylindrical,  about  2  in.  long.  Wood 
white,  valuable  as  timber.  This  replaces  the  preceding  species  east 
of  the  Cascade  Mountains. 


Vin.    TSU'GA,  Hemlock  Spruce 

Similar  to  the  true  spruces  but  with  flatter  leaves,  having 
short  petioles  joined  to  a  hard,  woody,  persistent  base.  Seeds 
resinous  on  the  surface  and  cones  smaller.  Tall  trees  of 
pyramidal  outline  and  slender,  drooping  branchlets. 

a.  T.   heterophyTla  Sargent.     Bark  thick,  reddish  brown.     Cones 
less  than  an  inch  long,  ovate.     This  is  found  along  the  coast  from 
northern  California  to  Alaska  and  is   one  of  the   most  important 
timber  trees. 

b.  T.  Mertensia'na  Sargent  (T,  Pattonia'na).     PATTON'S  SPRUCE, 
HEMLOCK  SPRUCE.     Trees  with  thick,  cracked  bark,  reddish  gray 
and  apt  to  be  scaly.     Cones  long  and  slender,  2-3  inches  in  length. 
Seeds  with  wings  almost  twice  their  length.     This  is  shrubby  at 
great  elevations,  but  when  favorably  situated  becomes  a  tree  more 
than  a  hundred  feet  high.     The  apex  is  slender  and  pendent  and  the 
trunk  generally  slopes  at  base.     It  is  found  in  the  higher  Sierra 
Nevada  Mountains  and  northward  to  Alaska,  where  it  grows  along 
the  coast. 

IX.    PSEUDOTSIFGA,  Douglas  Spruce 

Mowers  monoecious,  from  the  axils  of  last  year's  leaves. 
Staminate  clusters  subtended  by  conspicuous  involucres  of 
bud  scales  ;  pollen  scales  with  2  oblong  pollen  sacs  tipped 
by  an  awl-shaped  spur.  Fertile  clusters  near  the  ends  of 
branchlets,  dark  red  or  yellowish  green,  with  scales  concealed 
by  2-lobed,  long,  pointed  bracts.  Cones  oblong,  drooping, 
maturing  in  one  year,  but  remaining  on  the  trees  after  the 
seeds  have  fallen  out.  The  leaves  are  flat  and  2-ranked,  on  short 
petioles.  This  can  easily  be  distinguished  from  other  conifers 
by  the  fringe-like  bracts  over  the  scales  of  the  drooping  cone. 


18  KEY   AND   FLORA 


P.  mucrona'ta  Sudw.  (P.  Douglas'ii  Carr),  (incorrectly  called 
OREGON  PINE  and  RED  FIR).  This  is  found  in  California  and 
Oregon,  and  usually  grows  near  streams.  It  becomes  a  very  tall 
tree.  The  wood  is  yellow  or  reddish  and  rather  coarse,  and  the  bark 
is  fissured. 

X.    PI'NUS,  Pine 

Monoecious.  Staminate  clusters  crowded  at  the  base  of  the 
young  shoots  of  the  season  ;  pollen  scales  spirally  arranged, 
forming  an  elongated,  cylindrical  cluster,  with  2  pollen  sacs 
to  each  scale  (Fig.  1,  #).  Fertile  flowers  of  spirally  arranged 
carpel  scales  on  an  axis,  each  scale  bearing  2  ovules  at  base 
(Fig.  .1,  3).  Fruit  a  cone  ripening  the  second  year,  but  often 
remaining  unopened  on  the  tree  several  years.  Leaves  ever- 
green, needle-shaped,  in  bundles  of  from  2-5,  enclosed  in  a 
sheath  of  membranous  scales  (Fig.  1,  d).  Seeds  generally 
winged  (Fig.  1,  4). 

a.  P.  Lambertia'na  Dougl.     SUGAR  PINE.     Leaves  5  in  a  sheath, 
3-4  in.  long.     Cones  long,  narrow,  cylindrical,  from  a  foot  to  more 
than  2ft.  long  when  fully  grown,  pendent  at  the  ends  of  the  branches 
the  second  year,  the  scales  without  knobs  or  prickles.    This  is  a  very  tall 
and  large  pine,  with  the  upper  branches  widely  spreading  and  with 
irregular  and   picturesque  outlines.     It  is  common   in  the  Sierra 
Nevada  Mountains  at  moderately  high  elevations  and  on  most  of 
the  high  peaks  of  the  Coast  Mountains,  extending  into  Washington 
and  Oregon. 

b.  P.  montic'ola  Dougl.     SMALL  SUGAR  PINE.     This  is  a  smaller 
tree  than  the  preceding  but  similar,  with  leaves  5  in  a  sheath,  about 
2  in.  long.     Cones  3—8  in.  long,  with  the  scales   without  knobs  or 
prickles,  reflexed  when  the  seeds  are  ripe.     This  is  common  in  the 
higher  Sierra  Nevada  Mountains,  especially  northward,  and  extends 
into  Oregon  and  Washington  at  lower  elevations. 

c.  P.  pondero'sa   Dougl.     YELLOW  PINE.     Leaves   3   in  a  sheath, 
5-11  in.  long,  rather  thick.      Cones  oval,  3-5  in.  long,  sessile,  spread- 
ing or  recurved,  generally  several  together ;  scales  with  stout  prickles. 
Wings  on  the  seeds  not  quite  an  inch  long,  widest  above  the  middle. 
This  is  one  of  the  largest  pines  of  the  coast.     It  is  found  in  the 
mountains  in  the  same  region  as  the  Sugar  Pine  but  more  widely 
distributed.     The  variety  Jeffrey!  is  found  generally  at  higher  eleva- 
tions and  has  longer,  coarser  leaves,  and  much  larger  cones.     This 
is  the  most  widely  distributed  species  and  one  of  the  most  prized 
timber  trees. 


GYMNOSPERMS 


19 


d.  P.  contorta  Dougl.  Leaves  2  in  a  sheath,  short.  Cones  small 
and  slender,  1-3  in.  long,  whorled,  oblique,  often  remaining  closed 
for  many  years ;  scales  with  strong  knobs  and  delicate  prickles.  This  is 
a  small  tree.  It  is  found  along  the  coast  from  California  to  Alaska. 


FIG.  1.  — Scotch  Pine  (P.  sylvestris). 

1,  a  twig  showing  :  a,  staminate  catkins  ;  6,  pistillate  catkins  ;  c,  a  cone  ;  d,  needles. 
2,  an  anther  :  a,  side  view  ;  b,  outer  surface.  3,  a  carpel  scale  :  a,  inner  surface  ; 
6,  outer  surface.  4,  a  cone  scale,  a  seed  wing,  and  a  seed.  5,  section  of  a  seed, 
showing  the  embryo.  1  is  natural  size  ;  the  other  parts  of  the  figure  are  magni- 
fied by  the  amount  indicated  by  comparison  with  the  vertical  line  alongside  each. 

The  variety  Murrayana  is  a  tall,  straight  tree,  growing  in  the  moun- 
tains and  known  as  Lodge-pole  Pine,  from  the  use  made  of  the 
slender,  straight  stems  by  the  Indians.  It  is  widely  distributed  and 
variable. 


20  KEY    AND   FLORA 

e.  P.  radia'ta  Don  (P.  insig'nis  Dougl.).  MONTEREY  PINE.  Leaves 
3  in  a  sheath,  4-6  in.  long,  slender,  lax,  closely  serrate,  bright  green, 
densely  clustered.  Cones  encircling  the  stem,  deflexed  on  short  stems, 
pointed,  curved  inwards,  owing  to  the  difference  between  the  inner  and 
outer  scales.  The  cones  remain  on  the  tree  two  or  more  years  without 
opening.  This  pine  is  most  extensively  cultivated  in  California  for 
wind-breaks.  It  grows  nearly  100  ft.  in  height. 

/  P.  attenua'ta  Lemmon  (P.  tubercula'ta  Gord.).  KNOB-CONE  PINE. 
Leaves  3  in  a  sheath,  4-7  in.  long.  Cones  in  whorls,  often  with  several 
whorls  in  a  bunch,  strongly  rejlexed  on  short  stems,  oblique,  tapering  to 
a  very  narrow  base,  with  the  apex  pointed  ;  the  outer  scales  are 
enlarged  and  conical,  the  inner  Jlatter,  both  tipped  with  stout  prickles. 
The  cones  persist  on  the  stems  and  branches  many  years  without 
opening.  This  is  a  small  tree  and  often  begins  to  bear  cones  when 
a  foot  or  two  high.  It  is  found  in  the  Coast  Mountains  and  in  the 
foothills  of  the  Sierra  Nevada  Mountains. 

g.  P.  Sabinia'na  Dougl.  NUT  PINE,  BULL  PINE,  DIGGER  PINE. 
Leaves  3  in  a  sheath,  8-12  in.  long,  light  glaucous  green,  slender,  droop- 
ing;  cones  massive,  short-oval,  6-10  in.  long,  5-7  in.  in  diameter 
near  the  base,  deflexed  on  short,  stout  stems  ;  scales  with  stout,  claw-like 
projections.  The  nuts  are  edible  and  have  a  stony  shell,  and  formed 
an  important  part  of  the  food  of  the  Digger  Indians.  This  tree 
generally  has  loose  spreading  branches  and  is  very  graceful.  The 
long  light-green  foliage  easily  distinguishes  it  from  other  pines.  The 
cones  often  remain  on  the  branches  several  years  after  the  seeds  have 
fallen  out.  This  pine  is  the  most  common  in  the  foothills  of  the 
Sierra  Nevada  Mountains  and  in  the  valleys  of  the  Coast  Mountains. 


CLASS  II.  —  AN'GIOSPERMS 

Plants  with  a  closed  ovary,  in  which  the  seeds  are  matured. 
Cotyledons  1-2. 

SUBCLASS  I.  — MONOCOTYLED'ONOUS   PLANTS 

Stems  with  the  nbro-vascular  bundles  scattered  amid  the 
parenchyma  cells  (/.  Fig.  52  ;  e.  Fig.  54)  ;  in  perennial  plants 
no  annual  rings  of  wood.  Leaves  usually  parallel-veined, 
alternate,  nearly  entire.  Parts  of  the  flower  generally  in 
threes  (never  in  fives).  Cotyledon  1. 


MONOCOTYLEDONOUS   PLANTS 


21 


GRAMIN'EJE.     GRASS  FAMILY 

Mostly  herbs,  with  usually  hollow  stems,  closed  and  enlarged 
at  the  nodes.  Alternate  leaves,  in  2  ranks,  with  sheathing 
bases,  which  are  split  open  on  the  side  opposite  the  blade. 
The  flowers  are  nearly  or  quite 
destitute  of  floral  envelopes, 
solitary,  and  borne  in  the  axils 
of  scaly  bracts  called  glumes, 
which  are  arranged  in  2  ranks 
overlapping  each  other  on 


FlG.  2.  —  Diagram 
of  Inflorescence 
of  a  Grass. 

g,  sterile  glumes ; 
y;,,;i  flowering 
glume; /»2>ascaly 
bract  (palea) ;  e, 
transparent 
scales  (lodicules) 
at  the  base  of  the 
flower;  B,  the 
flower. 


FIG.  3.  — Fescue-grass  (Festuca 

pratensis). 

A,  spikelet  (compare  Fig.  2)  ;  /?,  a 
flower,  the  lodicules  in  front  and 
the  palea  behind ;  C,  a  lodicule  ; 
/),  ovary. 


1-many-flowered  spikelets  ;  these  are  variously  grouped  in 
spikes,  panicles  (/.  Figs.  136,  A,  B,  C  ;  e.  Fig.  183),  and  so  on. 
The  fruit  is  a  grain. 


22 


KEY   AND   FLORA 


(The  family  is  too  difficult  for  the  beginner,  but  the  struc- 
ture and  grouping  of  the  flowers  may  be  gathered  from  a 
careful  study  of  Figs.  2,  3.) 


FIG.  4.  —  Inflorescence,  Flower,  and  Seed  of  a  Sedge. 

(Great  Bulrush,  Scirpus  lacustris.) 

A,  magnified  flower,  surrounded  by  a  perianth  of  hypogynous  bristles  ;  J), 
seed  ;  C,  section  of  the  seed,  showing  the  small  embryo  enclosed  in 
base  of  the  endosperm. 


the 
the 


CYPERA'CE^.     SEDGE  FAMILY 

Grass-like  or  rush-like  herbs,  with  solid,  usually  triangular 
stems,  growing  in  tufts.  The  sheathing  base  of  the  generally 
3-ranked  leaves,  when  present,  is  not  slit  as  in  grasses.  The 


MONOCOTYLEDONOUS  PLANTS  23 

flowers  are  usually  somewhat  less  enclosed  by  bracts  than 
those  of  grasses  ;  the  perianth  is  absent  or  rudimentary ; 
stamens  generally  3  ;  style  2-cleft  or  3-cleft. 

The  flower  cluster  and  the  flower  may  be  understood  from 
an  inspection  of  Fig.  4. 

The  species  are  even  more  difficult  to  determine  than  those 
of  grasses. 

ARA'CEJE.     ARUM  FAMILY 

Smooth,  perennial  herbs,  generally  growing  in  wet  places. 
Leaves  large,  radical  or  alternate.  Flowers  sessile,  crowded 
on  a  spadix  which  is  surrounded  by  a  broad  sheathing  spathe. 
Perianth  in  our  representative  with  4  divisions.  Ovary 
2-celled  and  2-ovuled.  Fruit  consisting  of  berries  which 
coalesce  on  the  spadix. 

LYSICHI'TON,  Skunk  Cabbage 

Leaves  large,  1-3  ft.  long  and  often  a  foot  broad,  growing 
from  a  thick  rootstock.  Spadix  at  first  covered  by  a  yellow- 
ish green  spathe,  later  extending  beyond  it  on  a  stout 
peduncle.  Flowers  covering  the  spadix.  Stamens  4,  oppo- 
site the  segments  of  the  perianth,  with  2-celled  anthers 
opening  upwards. 

L.  Kamtschatcen'sis  Schott.  This  is  found  in  swamps  from 
northern  California  to  Alaska.  It  blooms  in  May  and  June.  It  is 
a  beautiful  plant  with  large,  broad  leaves,  covering  the  swamps,  but 
it  has  a  strong  and  disagreeable  odor,  from  which  the  common 
name  is  derived. 


LILIA'CEJE.     LILY  FAMILY 

Her.bs.  Flowers  regular  and  symmetrical,  with  their  parts 
3  or  some  multiple  of  3.  Ovary  3-celled,  free  from  the 
perianth.  Fruit  a  capsule  or  berry.  Seeds  with  endosperm 
(/.Fig.  5;  e.  Fig.  8,1). 


24  KEY   AND   FLORA 


I.    AI/LIUM,  Wild  Onion 

Plants  with  the  odor  and  taste  of  onion.  Scape  from  a  coated 
bulb.  Involucre  with  papery  bracts.  Pedicels  not  jointed 
under  the  flowers.  Perianth  rose-color  or  white.  Stamens  6, 
with  filaments  broadening  towards  the  base,  attached  to  the 
perianth.  Ovules  2  in  each  cell  of  the  ovary,  rarely  all  ripen- 
ing. (There  are  many  species,  difficult  to  determine.  The 
most  common  are  given.) 

a.  A.  serra'tum  Watson.     Scape   nearly  a  foot   high.      Perianth 
dark  rose-color,  with    divisions   in  2   sets,  dissimilar.     Ovary  with 
wart-like  crests  at  summit.     Outer  bulb  coats  marked  with  a  horizontally 
zigzag  veining  which  tears  readily  along  the  veins.     This  is  common 
and  abundant  wherever  found. 

b.  A.   unifo'lium  Kellogg.      Scape   usually   2   ft.  or   more  high. 
Flowers  pale  rose-color  or  white,  from  10  to  30  in  the  umbels.     Ovary 
smooth  at  summit.     Bulb  propagating  by  a  side  offshoot,  the  white  outer 
coats  marked  by  a  delicate,  complicated  veining.     This  grows  in  wet 
places  and  generally  has  more  than  one  leaf. 

c.  A.  acumina'tum  Hook.      CRIMSON-FLOWERED  ONION.      Scapes 
4-6  in.  high,  from  a  bulb  with  outer  coats,  not  fibrous,  but  marked 
with  hexagon^!  or  quadrangular  venation.     Leaves  narrowly  linear. 
Bracts  of  the  involucre  2.     Flowers    crimson,  on  pedicels  nearly  an 
inch  long,  in  erect  umbels.     Segments  of  the  perianth  recurved,  with  long, 
pointed  tips,  the  inner  ones  wavy  and  minutely  serrate.    Generally  grow- 
ing in  adobe  soil,  blooming  in  spring  and  early  summer.    It  is  found 
chiefly  on  the  eastern  side  of  the  Sierra  Nevada  Mountains  and 
north  to  British  Columbia. 

d.  A.  attenuifo'lium  Kellogg.     Scape  slender,  from  6  in.  to  more 
than  a  foot   high.     Leaves   narrow,    becoming  thread-like    at   tip. 
Bracts  of  the  umbel  2,  short,  acute.     Umbel  with  many  white  flowers. 
Segments  of  the  perianth  pointed,  longer  than  the  stamens.     Ovary 
tvith  6  crests  at  summit.     Bulb  coats  often  reddish,  with  a  fine,  wavy 
veining.     This  is  found  in  wet  places  in  the  Coast  Mountains,  in 
the  Sierra  Nevada  Mountains,  and  it  extends  into  Oregon. 

e.  A.  falcifo'lium  H.  and  A.     Scape  low,  flat,  2-edged.     Leaves  2, 
flat,  broad,  sickle-shaped.     Bracts  2.     Flowers  deep  crimson,  the  seg- 
ments of  the  perianth  edged  with  minute,  glandular  teeth.     Capsule 
pointed  with  short,  narrow  crests.     Bulb  large  and  globular,  the  mark- 
ings on  the  coats  not  distinctive.    This  is  found  in  sandy  or  gravelly 
places  on  the  hills  of  the  Coast  Mountains,  especially  northward, 
extending  to  Oregon. 


MONOCOTYLEDONOUS  PLANTS  25 


H.    MUIL'LA 

Similar  to  Allium,  but  without  the  odor  and  taste.  Flowers 
greenish  yellow.  Bracts  of  the  umbels  from  4  to  6,  linear- 
lanceolate.  Ovules  8-10  in  each  cell  of  the  ovary. 

M.  maritlma  Watson.  This  is  found  in  the  interior  of  the  state 
and  along  the  coast,  frequently  growing  in  alkaline  soil.  The 
flowers  have  a  delicate  perfume. 


IH.    BLOOME'RIA,  Golden  Stars 

Perianth  of  6  nearly  equal,  spreading  divisions  ;  light 
orange,  with  a  dark  midnerve  of  2  closely  parallel  lines. 
Pedicels  jointed  under  the  perianth.  Stamens  6,  with  slender 
filaments  nearly  as  long  as  the  perianth,  —  each,  at  base,  at- 
tached to  a  short  %-toothed,  hairy  appendage ;  these  uniting  to 
form  a  cup  at  the  base  of  the  perianth.  Ovules  several  in  each 
cell  of  the  ovary. 

B.  au'rea  Kellogg.  GOLDEN  BLOOMERIA,  GOLDEN^STARS.  Bulb 
small,  densely  covered  with  brownish  fibers.  Flowers  usually  nu- 
merous in  the  umbel.  Capsule  beaked  with  the  persistent  style. 
From  Monterey  to  San  Diego,  and  abundant  wherever  found. 


IV.      BRODUS'A,   GENERALLY  KNOWN  AS   BRODLffiA, 

SOMETIMES  CALLED  Wild  Hyacinth 

Corm  coated  with  brownish  fibers  (sometimes  tissue-like), 
flat  on  the  bottom  when  the  old  part  is  removed.  Leaves 
generally  withering  soon.  Pedicels  of  various  lengths,  jointed 
under  the  perianth.  Flowers  withering  and  persisting,  white, 
blue-purple,  rose-color,  yellow,  or  scarlet  ;  in  shape  tubular, 
rotate,  or  funnel-form.  Stamens  in  2  sets,  3  or  6,  attached  to 
the  tube  of  the  perianth,  often  with  wing-like  appendages  on 
the  filaments  ;  when  3,  alternating  with  petal-like  staminodia. 
(Staminodia  are  filaments,  usually  broadened,  without  anthers.) 

(There  are  5  subgenera  which  Professor  Greene  regards 
as  genera;  so,  to  avoid  confusion,  the  species  are  arranged 
under  the  subgenera.) 


26  KEY   AND   ELORA 

SUBGENUS  DICHELOSTEMTMA.  Perianth  tubular,  3  stamens  with 
erect  anthers  and  wing-like  appendages  on  each  side  of  the  filaments,  the 
other  3  free  or  reduced  to  staminodia. 

a.  B.   capita'ta   Benth.     GRASS    NUTS,    BRODI.EA,    WILD    HYA- 
CINTH   (often    incorrectly   WILD    ONIONS).      Flowers    blue-purple 
(rarely  white),  in  a  close  umbel,  like  a  head.     Bracts  of  the  invo- 
lucre membranous,  dark  purple.      Stamens  with  anthers  6,  the  inner 
anthers  nearly  sessile  with  wing-like  appendages,  the  outer  free,  on  short 
filaments;  the  appendages  of  the  inner  anthers  form   a  crown  in  the 
throat  of  the  perianth.    This  is  abundant  and  widely  distributed.    The 
children  eat  the  bulbs  and  call  them  "  grass  nuts." 

b.  B.  volu'bilis   Baker    (Strophilir'ion).       TWINING     HYACINTH. 
Perianth   rose-color,  with  a  6-angled  tube   nearly  as  long-   as  the 
divisions.      Three  stamens  with  anthers   and   wing-like    appendages,  3 
emarginate  staminodia.     Scape  long,  twining   snake-like    around  other 
stems.     The  color  of  the  flowers  and  shape  of  the  umbel  might  lead 
one  to  suppose  this  a  wild  onion.     It  is  common  in  the  foothills  of 
the  Sierras  and  is  found  also  in  the  Coast  Mountains. 

c.  B.    coccin'ea    Gray     (Brevoor'tia).       FIRECRACKER    FLOWER. 
Perianth  with  a  scarlet  tube  nearly  an  inch  long,  and  6  short  and 
broad   green    divisions.      Three   stamens   with  wing-like    appendages, 
3  staminodia.      The  staminodia  and  appendages  are  yellow.      The 
scape  is  long  apd  wavy,  but  not  twining.      These  brilliant  flowers 
hang,   as  if  too   heavy  to  stand   erect   on   their  slender   pedicels. 
Northern  California. 


SUBGENTJS  HOOK'ERA.  Perianth  tubular-funnel-shaped  with  a 
spreading  border.  Flowers  purplish  blue,  lighter  colored  at  base,  thick 
in  texture.  Pedicels  unequal.  Stamens  3,  with  erect  anthers  alternating 
with  3  petal-like  staminodia. 

d.  B.  grandiflo'ra  Smith.     Scape  from  a  few  inches  to  a  foot  in 
height.     Pedicels  3-10,  curved  outwards  and  upwards,  from  1  to  4  in. 
long.     Anthers  twice  as  long  as  the  slender  filaments.     Staminodia 
white,  tongue-shaped,  as  long  as  the  anthers.     The  flowers  of  this  are 
sometimes  nearly  an  inch  long.     This  blooms  in  summer  later  than 
other  species  growing  in  the  same  localities.     Quite  common. 

e.  B.  terres'tris  Kellogg.     GROUND  LILY.     Scape  scarcely  appear- 
ing above  the  surface  of  the  ground.     Flowers  smaller  than  the 
last.     Staminodia  yellowish,  emarginate,  folded  backwards.     Common 
in  central  California  and  extending  northwards. 

SUBGENUS  CALLIPRO'RA.  Stamens  6,  with  versatile  anthers. 
Filaments  attached  to  the  throat  of  the  perianth,  winged  their  entire  length, 
3-forked  at  top,  with  the  anther  on  the  middle  prong. 


MONOCOTYLEDONOUS  PLANTS  27 

/.  B.  ixioi'des  Watson.  GOLDEN  BRODIJEA.  Perianth  funnel- 
form,  with  short  tube  and  spreading  divisions  which  are  yellow  with 
a  brown  midvein.  Capsule  on  a  stipe. 

SUBGENUS  TRITELE1A.  Stamens  6,  3  on  the  throat,  3  below  on 
the  tube,  with  no  appendages  on  the  filaments.  Anthers  versatile.  Capsule 
on  a  stipe. 

g.  B.  lax'a  Watson.  GRASS  LILIES,  ITHURIEL'S  SPEAR,  BLUE 
MILLA.  Scape  erect  from  1  to  2  ft.  high.  Flowers  usually  many,  on 
pedicels  2-4  in.  long,  blue  to  violet  (sometimes  white).  Perianth 
funnel-form,  narrow  at  base.  Capsule  on  a  prominent  stipe.  This  is 
common  and  very  lovely.  The  flowers  are  sometimes  an  inch  or 
more  long.  From  Kern  County  to  northern  Oregon. 

h.  B.  Douglas'ii.  Scape  stout,  erect,  a  foot  or  two  high.  Leaves 
keeled.  Flowers  blue,  on  short  pedicels.  Perianth  broadly  tubular, 
with  lobes  about  as  long  as  the  tube.  Oregon  and  Washington. 

SUBGENUS  HESPEROCOR'DUM.  Stamens  6,  filaments  without  ap- 
pendages, equal,  dilated,  and  united  at  base. 

i.  B.  lac'tea  Watson.  Scape  slender,  from  1  to  2  ft.  high.  Flowers 
numerous,  on  pedicels  from  1  to  2  in.  long.  Perianth  funnel-form,  thin 
in  texture,  white  with  a  green  midvein  on  each  division.  Anthers 
yellow  or  purple,  erect.  Capsule  almost  round,  beaked  by  the  pointed 
style,  stipitate.  In  northern  California  and  north  to  Washington. 


V.    LII/IUM,  True  Lilies 

Flowers  in  racemes  or  whorls  on  tall,  leafy  stems.  Bulbs 
formed  of  thick,  lanceolate  scales.  Perianth  deciduous,  funnel- 
form,  with  6  nearly  equal,  spreading  divisions.  Anthers  linear, 
versatile,  on  long  filaments.  Ovary  sessile.  Fruit  a  pod,  with 
2  rows  of  flat  seeds  in  each  cell.  Leaves  often  in  whorls, 
net-veined.  Bracts  leaf-like.  Nectary  a  narrow  groove. 

a.  L.  Washingtonia'num  Kellogg.  WASHINGTON  LILY.  Stems 
simple,  from  2  to  5  ft.  high.  Leaves  in  whorls  of  from  6  to  10, 
oblanceolate.  Flowers  large,  pure  white,  or  dotted  with  purple,  fading 
purplish,  from  2  to  20,  hanging  on  ascending  pedicels  in  a  simple  or 
compound  raceme.  Perianth  divisions  not  recurved.  The  flowers  are 
fragrant,  from  3  to  4  in.  long  and  spreading  nearly  as  wide.  This 
fine  lily  generally  grows  in  the  shade,  in  the  higher  Sierra  Nevada 
Mountains  and  in  Oregon. 


28  KEY  AND  FLORA 

b.  L.  pardali'num  Kellogg.     TIGER  LILY,  LEOPARD  LILY.     Stems 
simple,  3-7  ft.  high,  from  a  bulb  like  a  thick  rootstock,  forming 
clumps.     Leaves   acuminate    in  whorls    of  from   9  to   15,  lanceolate, 
pointed,  3-nerved,  varying  in  width.    Flowers  in  racemes,  the  lowest 
often  whorled,    nodding  at   the    ends   of  long    spreading   pedicels. 
Perianth  orange  below,  spotted  with  reddish  purple ;  segments  curled 
backwards.     Anthers  red.     This    is  frequent  along  streams  under 
the  trees,  in  the  Coast  and  Sierra  Nevada  Mountains. 

c.  L.  Humbold'tii  Roezl.  and  Leicht.     HUMBOLDT'S  LILY,  TIGER 
LILY.     Stems  stout,  purplish,  4—8  ft.  high,  from  bulbs  2-6  in.  in 
diameter  composed   of   fleshy,  ovate-lanceolate  scales  2-3  in.  long. 
Leaves  large,  with  undulate,  rough  margins,  in  4-6  whorls  and  with 
10-20    in   each    whorl.      Flowers   large,    drooping,    on    stout    widely 
spreading  pedicels  which  are  from  a  few  inches  to  nearly  a  foot  long. 
Segments   of  the  perianth   3-4   in.   long,   reddish   orange,   spotted  with 
purple,  curled  back.     Stamens  about  equaling  the  style,  anthers  red. 
Capsule  large,   sharply  6-angled.     This  blooms  in  summer  and  is 
frequent  in  the  foothills  of  the  Sierra  Nevada  Mountains  and  south 
to  near  San  Diego. 

d.  L.  par'vum  Kellogg.     SMALL  TIGER  LILY.    Stems  slender,  1  to 
more  than  6  ft.  high,  from  a  small  bulb  composed  of  short,  thick, 
jointed  scales.     Leaves  scattered  or  in  whorls,  2-5  in.  long.    Flowers 
small,  erect,  or  nearly  so,  on  slender,  almost  erect  pedicels.     Segments  of 
the  perianth  about  an  inch  long,  orange,  spotted  with  purple,  reddish  at 
the  recurved  spreading  tips.     Stamens  almost  as  long  as  the  style. 
Capsule  roundish,  less  than  an  inch  long.     This  is  frequent  in  the 
Sierra  Nevada  Mountains  and  north  to  Oregon. 

e.  L.  Columbia'num  Hanson.     Bulb  small,  with  fleshy  white  scales 
closely  folded  over  each  other.     Stems  slender,  2—3  ft.  high.     Upper 
and  lower  leaves  scattered,  the  others  in  whorls  of  5-several,  oblanceo- 
late.     Flowers  nodding,  few  or  many,  on  scattered,  slender,  curving 
pedicels.      Perianth    bright   orange  spotted  with  purple,  the  segments 
1-2  in.  long,   revolute.      Anthers  yellow.      Capsule    an   inch    long, 
6-angled.    This  beautiful  lily  is  common  in  Washington  and  Oregon 
and  is  found  in  northern  California. 

VI.    FRITILLA'RIA,  Mission  Bells,  Rice  Roots 

Stems  simple,  leafy.  Bulb  with  round,  thick  scales,  often 
like  grains  of  rice.  Flowers  in  racemes,  nodding  on  rather 
short  pedicels.  Perianth  bell-shaped  with  separate  divisions, 
nectary  a  shallow  pit. 

a.  F.  lanceola'ta  Pursh.  CHECKERED  LILY.  Leaves  in  from 
1  to  3  whorls,  lanceolate,  2-5  in.  long.  Flowers  on  slender  pedicels, 


MONOCOTYLEDONOUS  PLANTS  29 

checkered  variously  in  dark  purple  and  greenish  yellow.  Pods  with 
winged  angles.  Bulb  solid,  not  dividing  into  scales,  but  with  rice-like 
grains  over  the  whole  upper  surface.  In  the  Coast  Mountains  extend- 
ing to  British  Columbia. 

b.  F.  biflo'ra  Lindl.    CHOCOLATE  LILY.    Leaves  scattered  or  some- 
times whoiied.     Flowers  1—3,  brownish  red  or  sometimes  greenish 
purple.    Pod  angled  but  not  winged.    Bulb  composed  of  thick,  separable 
scales  and  without  rice-like  grains.     More  common  southward. 

c.  F.  recur'va  Benth.     Stem  rather  stout  and  tall,  generally  more 
than  a  foot  high.     Leaves  linear-lanceolate,  in  2  whorls  near  the 
middle  of  the  stem.     Flowers  1-9,  scarlet  spotted  with  yellow,  obtuse  at 
base.     This  is  found  in  the  Sierra  Nevada  Mountains  and  it  extends 
northward  into  Oregon. 

(1.  F.  coccin'ea  Greene.  This  is  similar  to  the  above,  but  the  Jlowers 
are  acute  at  the  base.  It  is  found  in  the  Coast  Mountains. 

e.  F.  atropurpu'rea  Nutt.  Stem  6  in.  to  a  foot  high.  Leaves  scat- 
tered or  whorled.  Flowers  dull  purplish  or  greenish,  often  imperfect, 
less  than  an  inch  across  when  expanded.  Pod  with  3  short  angles,  broad- 
est at  the  top.  From  northeastern  California  to  the  Columbia  River. 

/.  F.  pu'dica  Spreng.  Stems  3-8  in.  high.  Leaves  few,  scattered 
or  whorled.  Flowers  generally  solitary,  yellow  or  orange  and  tinged 
with  crimson.  Pod  oblong,  with  angles  obtuse.  From  east  of  the 
Sierra  Nevada  Mountains  to  British  Columbia. 


VII.    ERYTHRO'NIUM,  Dog-tooth  Violet,  Adder's  Tongue 

Scapes  from  an  oblong,  deep-seated  corm,  generally  with  a 
tooth-like  offshoot.  Leaves  broad,  often  mottled  with  brownish 
red,  generally  2  at  the  base,  spreading  in  opposite  directions. 
Flowers  one  or  several  in  an  umbel.  Perianth  nodding,  open 
bell-shaped,  of  6  recurved  divisions.  Stamens  6,  with  erect 
anthers  and  slender  filaments.  Pods  3-sided. 

a.  E.  gigante'um  Lindl.    Scape  from  10  to  15  in.  high.    Flowers  1-6 
in  an  umbel.     Leaves  often  mottled,  6-10  in.  long.     Flowers  cream- 
color,  often  tinged  with  pink  or  brown,  yellow  in  the  center.     Seg- 
ments 1-2  in.  long,  much  recurved.      In  the  Coast  Mountains  from 
Sonoma  County  to  Washington. 

b.  E.  Hartwe'gi  Watson.     Scape  shorter.     Leaves  generally  mottled, 
sometimes  3.    Flowers  pale  yellow,  orange  at  the  center,  with  segments 
1-1 1  in.  long,  recurved  but  little.     Flowers  on  slender  stems,  from  1  to  5, 
in  a  sessile  umbel.     This  is  found  in  the  Sierra  Nevada  Mountains. 

c.  E~  grandiflo'rum  Pursh.    Leave*  not  mottled.    Flowers  1-6,  yellow 
or  cream  color,  with  the  base  of  the  perianth  white.     Anthers  purple. 


30  KEY   AND   FLORA 

Pods  oblong,  narrowed  at  base.     This  is  common  in  Washington 
and  Oregon. 

VIII.    YUC'CA,  Spanish  Bayonet,  Soapweed 

Leaves  stiff  and  pointed  like  daggers,  growing  in  a  bunch. 
Flowers  in  a  raceme  or  panicle.  Perianth  of  6  thick  divisions, 
bell-shaped,  nodding.  Stamens  with  thick  filaments  attached 
to  the  base  of  the  perianth.  Ovary  sessile.  Stigmas  3,  united. 
Fruit  with  cells  incompletely  divided.  Seeds  black,  fiat,  2  rows 
in  each  cell. 

a.  Y.  Whip'plei  Torr.      Scape  4-12  ft.  high  and  about  2  in.  in 
diameter,  clothed  with  sharp-pointed  bracts  close  to  the  stem,  rising 
from  amidst  a  thick  bunch  of  narrow,  dagger-like  leaves.     Flowers 
in  a  panicle.     Segments  of  the  perianth  cream-color,  1-2  in.  long. 
The  plant  from  which  the  scape  springs  dies  after  fruiting ;  but  the 
dead  scapes  often  remain  standing  like  slender  white  posts  on  the 
hillsides. 

b.  Y.  arbores'cens  Torr.     This  is  the  tree  Yucca  of  the  Mojave 
Desert.     /.  Part  I,  Plate  VII. 

IX.    CALOCHOR'TUS,  Butterfly  Tulip^Mariposa  Lily 

Perianth  with  3  outer  segments  sepal-like,  the  3  inner  petal- 
like,  each  with  a  large  honey-gland  near  the  base,  densely  covered 
with  hairs.  Flowers  erect  or  drooping,  solitary,  in  racemes 
or  in  umbels,  beautifully  and  variously  colored.  Stamens  6, 
with  erect  anthers.  Seeds  in  2  rows  in  each  cell  of  the  ovary. 

a.  C.  alb'us   Dougl.      SATIN    BELL,    HAIRY   BELL,   ALABASTER 
TULIP.     Flowers  white,  or  pinkish  with  a  satiny  texture.     Segments 
of  the  perianth  curved  inwards,  forming  a  close  roundish  bell  in  shape 
something  like  a  sleigh  bell,  very  hairy  icithin.     Gland  crescent-shaped, 
almost  concealed  by  the  long  hairs  of  the  perianth.     Anthers  linear- 
oblong,  tipped  by  a  blunt  point.     Capsule  winged.     The  stems  are 
rather  tall,  leafy  and  branching,  bearing  numerous  flowers.     This 
grows  on  shady  banks  in  the  Coast  Mountains. 

b.  C.  pulchellus  Dougl.     GOLDEN  BELLS.     Flowers  shaped  as  the 
preceding,  yellow,  hairy  within  and  on  the  margins ;  flowers  rather  few. 
This  has  been  mistaken  for  the  next,  which  is  much  commoner. 

c.  C.  amab'ilis  Purdy.      DIOGENES'  LANTERN.      Similar  to  the 
above,  but  the  flowers  are  more  numerous,  smaller,  and  the  segments 
of  the  perianth  curve  inwards  so  much  that  they  overlap,  hairy  on  the 
margin  only.     This  is  common  in  northern  California. 


MONOCOTYLEDONOUS  PLANTS  31 

d.  C.  amoe'nus  Greene.    ROSY  BELLS.    This  is  similar  to  C.  amabilis 
in  form,  but  is  deep  rose-color.     It  grows  in  the  foothills  of  the 
southern  Sierra  Nevada  Mountains. 

e.  C.  Ben'thami  Baker.     YELLOW  STAR  TULIPS.     Flowers  bell- 
shaped  with  incurved  petals,  erect  when  open.     Petals  yellow,  densely 
covered  with  yellow  hairs,  the  gland  shallow  and  crescent-shaped 
above  the  brown  claw.     Capsules  nodding  on  slender  recurved  pedi- 
cels.    Low  slender  plants  with  from  2  to  (5  flowers.     Common  in  the 
Sierra  Nevada  Mountains  from  Mariposa  to  Siskiyou  County. 

/.  C.  Mawea'nus  Leicht.  MOUSE-EARS.  Flowers  less  than  an  inch 
in  diameter,  with  spreading  divisions,  erect  in  full  bloom,  white  or 
bluish.  Inner  divisions  of  the  perianth  densely  covered  with  long 
white  or  purplish  hairs.  Honey-gland  semicircular.  Anthers 
pointed.  Capsule  winged,  nodding.  Stems  low,  branched,  with 
from  3  to  6  flowers.  Common  in  northern  California.  Spring. 

g.  C.  el'egans  Pursh.  Scape  2-3-flowered,  generally  shorter  than 
the  single  grass-like  leaf.  Flowers  on  short  thread-like  pedicels 
which  are  not  much  longer  than  the  bracts.  Petals  about  ^  inch 
long,  white,  with  a  smooth  purple  spot  at  base,  covered  on  the  inside  with 
purple  down.  Pods  nodding.  The  roots  are  eaten  by  the  Indians. 
It  is  found  from  Oregon  and  Idaho  to  British  Columbia.  Spring. 

h.  C.  uniflo'rus  H.  &  A.  Scapes  erect  with  1-3  flowers.  Petals 
lilac,  an  inch  long,  wiftwfehe  upper  margin  denticulate  ;  gland  purple, 
densely  hairy,  with  a  few  scattered  hairs  on  the  petal  above.  Pods 
nodding.  This  is  found  in  middle  California  near  the  coast.  Spring. 

i.  C.  umbella'tus  Wood.  Scapes  low  and  often  decumbent. 
Flowers  generally  many  in  1-3  umbels  or  corymbs  on  long  slender 
pedicels.  Petals  white  or  tinged  with  pink  about  £  inch  long,  with 
some  hairs  on  the  lower  half ;  gland  covered  with  a  narrow  scale. 
Pods  obtuse  at  each  end,  nodding.  This  is  found  on  slopes  of  hills  in 
the  Coast  Mountains  of  middle  California.  Spring. 

j.  C.  nu'dus  Watson.  Low  and  slender  with  one  leaf.  Flowers 
1-6  in  one  umbel.  Petals  white  or  pale  lilac,  fan-shaped,  denticu- 
late on  the  upper  margin,  wholly  without  hairs ;  gland  shallow,  divided 
by  a  transverse,  denticulate  scale.  Pod  acute  at  each  end,  nodding. 
This  is  found  in  the  Sierra  Nevada  Mountains  from  the  Yosemite 
northward.  Early  summer. 

k.  C.  clava'tus  Watson.  Erect  stems  a  foot  or  two  high.  Flowers 
tulip-shaped,  erect.  Sepals  yellow  on  the  inner  side,  with  a  brownish 
spot  at  base,  greenish  on  the  outer  side.  Petals  yellow,  with  a  deep, 
round  gland  surrounded  by  yellow,  club-shaped  hairs.  Anthers  purple, 
obtuse.  Pod  erect,  narrowly  oblong,  with  thick,  obtusely  angled 
cells.  Southern  California.  Early  summer. 

1.  C.  Weed'ii  Wood.  Stem  branching,  leafy,  a  foot  or  more  high. 
Sepals  as  long  as  the  petals,  orange  on  the  inner  side  with  a  brown 


32  KEY   AND   FLORA 

spot  at  base.  Petals  1-1  £  in.  long,  fan-shaped,  deep  yellow,  dotted  and 
often  margined  with  brownish  purple,  covered  with  slender  yellow  or 
purple  hairs  ;  gland  small,  round,  densely  hairy.  Pod  erect,  narrowed 
to  the  top,  1£  in.  long.  The  variety  purpuras'cens  Watson  has  the 
petals  wholly  purple  or  Notched  with  purple.  These  are  common  in 
southern  California.  Early  summer. 

m.  C.  lu'teus  Dougl.  GOLDEN  TULIP.  Flowers  erect,  tulip-shaped, 
greenish  yellow,  and  variously  marked  with  brownish  purple,  slightly 
hairy  within.  Honey-gland  round  or  crescent-shaped,  densely  covered 
with  yellow  hairs.  Anthers  yellow,  linear-oblong,  obtuse.  Capsule 
erect,  narrowed  towards  the  top.  This  is  the  most  widely  distributed 
species  and  is  quite  variable.  Early  summer. 

n.  C.  lu'teus  var.  ocula'tus  Watson.  This  is  similar  to  C.  luteus, 
except  in  the  color  and  markings  of  the  petals.  They  are  white, 
cream,  or  purple,  with  a  central  brownish  spot,  which  is  usually  bordered 
with  yellow.  The  claw  is  yellow  or  purplish,  and  the  gland  is  narrowly 
crescent-shaped  and  covered  with  brownish  or  yellowish  hairs.  This 
includes  a  great  variety  of  color  3^grais,  and  has  a  wide  range.  It  is 
the  commonest  species  in  the  northern  Californian  valleys,  and  is 
found  in  both  the  Sierra  Nevada  and  Coast  Mountains  from  Fresno 
County  to  Oregon.  Early  summer. 

o.  C.  Nuttal'lii  Torr.  &  Gray.  Stem  alwayjubearing  a  small  bulb 
at  base.  Flowers  erect,  tulip-shaped,  1-seveiSwm  umbel-like  clusters. 
Sepals  ovate  lanceolate  with  papery  margins,  generally  yellowish 
within.  Petals  wliite  or  tinged  with  lilac,  with  a  purplish  spot 
above  the  yellow  base.  Gland  round  or  oblong,  densely  hairy,  and 
surrounded  by  long,  scattered  hairs.  Anthers  obtuse,  sagittate  at  base. 
Capsule  erect,  narrowed  upwards.  This  is  found  in  the  Sierra 
Nevada  Mountains,  especially  northward,  to  Oregon.  Early 
summer. 

p.  C.  venus'tus  Benth.  BUTTERFLY  TULIP.  Flowers  erect,  tulip- 
shaped,  white,  often  tinged  with  lilac,  or  purplish  throughout,  generally 
marked  with  a  red  spot  near  the  top  of  the  petals,  like  a  drop  of  blood. 
Honey-gland  narrowly  oblong,  hairy.  The  markings  above  the  glands 
are  beautiful  and  exceedingly  variable.  Pods  erect.  This  is  widely 
distributed  in  various  forms.  Early  summer. 

q.  C.  splen'dens  Dougl.  LILAC  TULIP.  Flowers  erect,  tulip-shaped, 
lilac  above  with  scattered  white  hairs,  paler  beneath.  Gland  round, 
densely  hairy,  sometimes  wanting.  Anthers  purple,  obtuse  or  acute. 
Pods  erect.  This  is  common  in  the  southern  parts  of  California. 
Early  summer. 

r.  C.  macrocar'pus  Dougl.  Stems  stout,  erect,  1-2  ft.  high,  with 
1-2  tulip-shaped  flowers.  Leaves  3-5,  narrow,  convolute.  Sepals 
about  as  long  as  the  petals,  narrowly  pointed,  lilac  on  the  inner  side. 
Petals  obovate  with  pointed  apex,  1|— 2  inches  long,  dark  lilac,  paler  at 


MONOCOTYLEDONOUS  PLANTS  33 

base  and  with  a  greenish  line  down  the  middle ;  gland  oblong,  densely 
hairy,  and  with  some  scattered  glandular  hairs  above.  Pods  erect, 
narrowed  upwards,  about  2  inches  long.  This  is  found  from  north- 
ern California  to  Washington  and  Idaho.  Summer. 

X.    CAMAS'SIA,  Camass 

Flowers  usually  deep  blue  in  a  simple  raceme  with  papery 
bracts.  Perianth  of  6  oblanceolate  segments,  spreading  open. 
Stamens  6,  on  the  base  of  the  perianth.  Style  slender,  with 
3  divisions.  This  has  a  coated  bulb  and  grows  in  swampy 
places.  The  flowers  are  rarely  white. 

CLesculen'ta  Lindl.  Scape  from  1  to  2  ft.  high.  Leaves  many,  near 
the^Dase,  keeled.  Style  as  long  as  the  perianth.  Stamens  shorter, 
with  awl-shaped  filaments  and  linear,  versatile  anthers.  The  bulbs 
are  eaten  by  the  Indians.  TluioArows  through  middle  California 
and  north  to 


XI.    CHLOROG'ALUM,  Soap  Plant,  Amole 

Stems  almost  leaqfcs  from  a  bulb,  either  fibrous  or  mem- 
branous-coated. Leaves  mostly  radical,  linear,  with  very  wavy 
margins.  Flowering  branches  widely  spreading,  with  the 
flowers  scattered  on  short  pedicels.  Perianth  of  6  oblong 
spreading  segments  which  persist  and  become  twisted  over  the 
ovary.  Stamens  6,  shorter  than  the  segments,  to  which  they 
are  adnate  at  base.  Capsule  3-lobed,  broadest  at  top,  with 
1  or  2  black  seeds  in  each  cell. 

C.  pomeridia'num  Kunth.  SOAP  PLANT,  AMOLE.  Bulb  large, 
covered  with  coarse  brown  fibers.  Leaves  6-18  in.  long,  and  nearly 
an  inch  wide.  Flowers  with  the  white  segments  veined  with  purple,, 
spreading  widely  from  the  very  base.  Pedicels  nearly  as  long  as  the 
flowers.  The  flowers  open  suddenly  in  the  afternoon,  and  are  con- 
spicuous on  the  leafless  stems.  The  bulb  is  used  as  a  substitute  for 
soap.  It  is  widely  distributed  and  blooms  in  summer. 

XII.     ZYGADE'NUS 

Stems  stout  from  a  deep  bulb.  Leaves  linear,  chiefly  near 
the  base  of  the  stem.  Flowers  in  racemes-  or  panicled  racemes. 
Perianth  greenish  white,  spreading  star-like,  with  a  greenish 


34  KEY   AND   FLORA 

yellow  gland  at  the  base  of  the  segments.     Stamens  nearly  free, 
with  filaments  at  first  recurved. 

a.  Z.  Fremon'ti  Torr.    Bulb  with  outer  coats  almost  black.    Stems 
from  a  few  inches  to  about  4  ft.  high.     Racemes  simple  or  compound, 
with  few  or  many  flowers.     Bracts  leaf-like.     Flowers  from  less  than 
a  half  inch  to  nearly  an  inch  in  diameter.     Perianth  entirely  free  from 
the  ovary ;  outer  segments  without  a  claw,  inner  with  claws.    Glands 
wavy.     Stamens  shorter  than  the  perianth.     Styles  short.     Capsule 
oblong,  3-lobed,  septicidally  dehiscent.     Spring. 

b.  1.   veneno'sus    Watson.      DEATH    CAMASS,    HOG'S    POTATO. 
Flowers  smaller  than  the  preceding,  generally  in   a  simple  raceme, 
the  lower  sometimes  staminate.      Segments  of  the  perianth  from 
triangular-ovate  to  elliptical,  with  blades  rounded  or  slightly  cordate 
at  base,  all  with  claws.     Capsule  oblong-ovate  with  2  seeds  iif^ach 
cell.     This  grows  in  wet  meadows  or  along  streams.     The  bulb  is 
said  to  be  poisonous,  except  to  hogs.     Spring. 

\        ^^---S* 

> 

XIII.    SMILACFNA,  False  Solomon's  Seal 

Stems  from  a  horizontal  rootstock,  siirmle,  leafy.  Flowers 
white,  very  small,  in  a  simple  or  comwumi  terminal  raceme. 
Anthers  versatile  on  awl-shaped  filament;!?.  Fruit  a  berry. 

a.  S.  amplexicau'lis  Nutt.     Stems  from  1  to  3  ft.  high.     Leaves 
broad,  half  clasping  the  stem.     Flowers  very  small,  in  an  oblong  or 
pyramidal  panicle.     Filaments  equaling  or  even  surpassing  the  divi- 
sions of  the  perianth  in  length  and  breadth.     Fruit  a  light-red  berry 
with  darker  dots.     This  is  common  in  rich,  shady  woods.     Spring. 

b.  S.  sessilifo'lia  Nutt.     Stems  not  so  tall.     Leaves  narrower  and 
lighter  green.    Raceme  simple,  with  star-like  flowers  on  spreading  pedicels. 
Stems  half  as  long  as  the  divisions  of  the  perianth.     Berry  green 
with  red  lines,  becoming  dark  red  when  fully  ripe.    This  is  common 
in  shady  woods.     Spring. 


XIV.    DIS'PORUM  (PROSAR'TES),  Fairy  Bells,  Drops  of  Gold 

Stems  from  a  spreading  rootstock,  widely  branching,  leafy. 
Leaves  alternate,  sessile  or  clasping.  Flowers  greenish  white, 
bell-shaped,  hanging  under  the  leaves  from  the  upper  axils. 
Fruit  an  orange  or  salmon-color  berry. 

«.  D.  Menzie'sii  Benth.  &  Hook.  Perianth  broad  at  base,  with 
divisions  somewhat  swollen.  Stamens  shorter  than  the  perianth. 


MONOCOTYLEDONOUS  PLANTS  35 

Style  3-cleft.  Leaves  ovate,  pointed,  often  cordate  at  base.  Fruit  a 
pear-shaped,  salmon-color  berry.  This  grows  along  the  banks  of 
streams  in  shady  woods  of  the  Coast  Mountains.  Spring. 

b.  D.   Hook'eri   Benth.   &  Hook.      Perianth    narrow   at   base,   with 
spreading  segments.     Stamens  equaling  or  surpassing  the  perianth. 
Leaves  ovate,  deeply  cordate  at  base,  rough  to  the  touch.     Fruit  an 
orange,  obovate  berry,  somewhat  pubescent.      This  grows  in   shady 
woods,  but  not  close  to  the  water.     Spring. 

c.  D.  trachyan'drum  Benth.  &  Hook.     This  is  similar  to  the  last, 
with  the  stamens  shorter  than  the  perianth.      Fruit  smooth,  with  a 
stout  beak.    This  grows  in  the  Sierra  Nevada  Mountains.     Spring. 

XV.    CLINTO'NIA 

very  short  from  a  rootstock.  Leaves  all  from  the 
base,  large,  oblanceolate,  sheathing,  with  many  veins  and  the 
veinlets  transverse.  Fj^^BrsHsolitary  or  on  a  scape-like 
peduncle,  in  umbels  orwhorls\  Perianth  of  6  oblanceolate 
divisions,  soon  falling  to  pieces.  Stamens  on  the  segments  of 
the  perianth  with  thread-like  filaments  and  versatile  anthers. 
Ovary  sessile,  2-3^^^ied.  Fruit  a  beautiful  blue  berry,  smooth 
and  glossy.  Seeds  rew  to  many. 

a.  C.  uniflo'ra  Kunth.      Covered  more  or  less  with  woolly  hairs. 
Stem  above  grom:d  scarcely  any.      Leaves  4-8  in.  long,  1-2   in. 
broad,  narrowed  at  base.    Peduncle  shorter  than  the  leaves,  bearing  1,  or 
rarely  2,  white Jlowers,  erect,  nearly  an  inch  across.     This  beautiful  and 
delicate  flower   grows    in    the   woods   and  is  found  from   northern 
California  to  British  Columbia.    It  blooms  in  late  spring  or  summer. 

b.  C.  Andrewsia'na  Torr.      Almost  smooth.      Stem  2-6  in.  long, 
bearing  5  or  6  large  leaves  nearly  a  foot  long  and  2-4  in.  wide,  bright 
green  and  very  luxuriant,  forming  a  circular  bunch  around  the  tall 
scape,  which  is  a  foot  or  two  high.     Flowers  generally  many,  in  umbels 
or  whorled  fascicles,  deep  rose-color,  pendent.     Perianth  broad  at  base, 
^-£  in.  long.     This  is  found  in  the  redwood  groves  and  is  in  bloom 
in  early  summer.     It  is  one  of  the  most  conspicuous  plants,  whether 
in  fruit  or  flower  or  with  only  its  tropical-looking  leaves. 

XVI.    STREP'TOPUS,  Twisted  Stalk 

Stems  from  slender,  creeping  rootstocks,  leafy,  glaucous, 
branching  in  pairs.  Leaves  alternate,  sessile,  lance-shaped, 
veiulets  transverse.  Flowers  usually  solitary  from  the  leaf 


36  KEY   AND   FLORA 

axils,  on  slender,  simple  or  forked  peduncles,  bell-shaped,  greenish 
white,  ivith  the  divisions  recurved  at  tip.  Fruit  a  round  berry 
with  3  cells  and  many  seeds. 

S.  amplexifolius  DC.  Stems  2-3  ft.  high.  Leaves  heart-shaped 
at  base,  2-5  in.  long,  rough  on  the  margins.  Perianth  about  half 
an  inch  long.  This  is  found  in  damp,  shady  places  from  northern 
California  to  Washington.  It  blooms  in  the  spring. 

XVII.     TRII/LIUM,  Wake  Robin 

Stems  erect,  naked  up  to  the  three  leaves  which  are  in  a 
whorl  under  the  flower.  Leaves  netted-veined,  large  and 
broad.  Perianth  withering,  but  not  falling.  Outer  divilfcs 
(sepals)  greenish,  inner  (petals)  colored.  Filaments  snort. 
Anthers  long,  erect.  Stigmas^jSgssile  on  the  sessile  ovary. 


a.  T.  sessile  L.     Leaves  broao>srpund-o;&ite,  often  mottled  with 
reddish  brown,  crowded.     Flowers  anoTTeaves  sessile.     Petals  white, 
rose-color,  deep  wine-color,  or  greenish  yellow.^JThis  is  common  in 
woods  near  the  coast.     It  is  exceedingly  \^yHL>le   in  the  size  and 
shape  of  the  leaves  and  parts  and  color  of^j^  flowers. 

b.  T.  ova'tum  Pursh.     Leaves  on  short  petioles,  ovate,  acute  or 
pointed.     Flowers  on  a  peduncle  from  1  to  3  in.  long.     Petals  white, 
turning  rose-color  as  they  fade.     This  has  the  same  range  as  the 
preceding,  but  is  usually  earlier  and  less  common.    *"' 

c.  T.  petiola'tum  Pursh.      Stem  short.      Leaves   ovate  to   kidney  - 
shaped,  with  petioles  equaling  or  longer  than  the  blade.    Flowers  sessile. 
Petals  narrowly  oblanceolate,  a  little  longer  than  the  sepals,  dull 
purple.     This  is  found  through  Oregon  and  Washington. 


AMARYLLIDA'CEJE.     CENTURY  PLANT  FAMILY 

Mostly  smooth  perennial  herbs,  sending  up  from  the  root  a 
scape  and  leaves  which  show  no  distinction  between  petiole 
and  blade.  Stamens  6.  Tube  of  the  6-parted  perianth  adnate 
to  the  S-celled  ovary.  Capsule  3-celled,  several  or  many  seeded. 
The  Chinese  Sacred  Lily,  the  Narcissus,  Jonquil,  and  Daffodils 
belong  to  this  family. 


MONOCOTYLEDONOUS   PLANTS  37 


I.    AGA'VE,  Century  Plant,  American  Aloe 

Plants  with  large,  thick,  spiny-pointed  and  spiny-toothed 
leaves.  The  flowers  are  numerous  on  short  bracted  pedicels, 
in  spikes  or  panicles,  at  the  summit  of  a  tall  woody  scape 
clothed  with  bracts.  The  perianth  is  thick  and  fleshy,  tubular 
or  bell-shaped,  with  the  6  divisions  nearly  equal.  Filaments 
bent  in  the  bud,  but  becoming  straight  and  extending  beyond 
the  perianth.  Capsule  leathery,  with  numerous  flattened  black 
seeds.  Different  species  of  Century  Plants  are  common  in 
cultivation,  and  several  species  are  native  in  desert  regions. 
It  blooms  in  California  when  10  to  20  years  old.  "Pulque," 
a  Mexican  drink,  is  made  from  the  sap  of  some  species. 

NARCIS'SUS,  Narcissus,  Jonquil 

a  cup-shaped  crown  at  the  throat  of  the  perianth. 
Tube  afatr' perianth  somewhat  cylindrical,  the  6  divisions 
of  the  border  widely  spreading.  Stamens  6,  inserted  in  the 
tube.  Scapes  with  1  ^o  several  flowers  from  a  thin,  dry 
spathe. 

N.  Tazet'ta.  CHINESE  SACRED  LILY.  Flowers  white,  with  yellow 
cup ;  fragrant.  Leaves  and  scapes  from  a  large  bulb,  like  an  onion. 
This  is  cultivated  especially  by  the  Chinese  and  usually  grows  in 
water.  It  is  in  bloom  during  the  winter,  about  the  time  of  the 
Chinese  New  Year,  and  can  readily  be  obtained  for  class  study. 


IRIDA'CEJE.     IRIS  FAMILY 

Herbs  with  equitant  2-ranked  leaves.  Flowers  showy, 
perfect.  Tube  of  the  perianth  attached  to  the  ovary,  which 
is  enclosed  by  spathe-like  bracts.  Stamens  3,  with  anthers 
turned  outwards.  Style  1,  stigmas  3,  often  petal-like.  Capsule 
3-celled  and  many-seeded. 

I.     I'RIS,  Blue  Flag,  Fleur  de  Lis,  Flower  de  Luce 

Sepals  8,  turned  backwards,  larger  than  the  3  erect  petals. 
Stamens  3,  distinct,  borne  on  the  sepals.*  Anthers  long,  and 


38  KEY   AND   FLORA 

covered  by  the  petal-like  branches  of  the  style.     Perennials 
with  dagger-shaped  leaves  and  large  rootstocks. 

a)  I.  macrosi'phon  Torr.  Stems  low,  forming  mats  of  bright  green, 
row,  erect  leaves,  amid  which  the  flowers  arise,  overtopped  by  the 
leaves.  Perianth  with  a  slender  tube  from  1  to  4  in.  long,  easily  break- 
ing. Flowers  dark  blue,  rarely  cream-color.  % 

b.  I.  Douglasia'na  Herbert.     Taller  than  the  last,  but  also  growing 
in  mats.     Leaves  dark  green,  rose-color  at  base,  laxly  spreading. 
Stems  bent  about  the  middle.     Tube  of  the  perianth  slender,  an  inch 
or  more  long.     Flowers  variable  in  color ;   cream,  rose-color,  violet, 
and  purplish  blue.     This  is  the  most  widely  distributed  species. 

c.  I.  longipet'ala  Herbert.     Stems  stout,  more  than  a  foot  high. 
Leaves  glaucous.      Flowers  larger   than   the  preceding.      Perianth 
funnel-form  at  base,  sessile  on  the  ovary.     Sepals  from  2  to  3  in.  long, 
beautifully  veined  with  yellow  and  violet.    Petals  shorter.     Petal-like 
branches  of  the  style  with  broad  crests.     This  Iris  covers j^res  of 
ground  in  low  places  near  San  Francisco.  \jr^ 

d.  I.  Missourien'sis.     Stems  slender,  the  few  leave sJmorjj&T  than 
the  stem.     Bracts  papery,  dilated.     Flowers  blue,  geneTSfffy  2  in  a 
spathe.     Sepals  and  petals  2  or  3  in.  long,  with  narrow  claws.    This 
grows  in  moist  or  wet  places  and  is  widely  distributed.     It  blooms 
in  spring. 

II.     SISYRI1TCHIUM,  Blue-eyed  Grass,  Star-eyed  Grass 

Perianth  6-parted,  with  the  spreading  divisions  all  alike. 
Stamens  monadelphous.  Stigmas  3-cleft,  very  slender,  usually 
twisted  together.  These  are  small  grass-like  perennials,  with 
pretty  flowers  that  soon  wither,  borne  on  slender  scapes. 

a.  S.  bel'lum  Watson.     BLUE-EYED  GRASS.     Stems  usually  about 
a  foot  high.     Leaves  shorter.     Spathes  2,  nearly  equal,  enveloping 
the  flowers  in  bud.     Flowers  J^-7,  purplish  blue,  yellow  at  the  center. 
Divisions  3-toothed  or  tipped  with  a  point.     Stamens  with  the  filaments 
united  to  the    anthers.      Stigmas    short,   hardly  apparent.      Capsule 
globular.     This  is  common  in  damp  places. 

b.  S.  grandiflo'rum  Dougl.    Scapes  about  a  foot  high.    Spathe  with 
1-4  flowers,  flattened  but  not  winged,  surpassing  the  leaves.     Bracts 
broad,  unequal,  the  larger  exceeding  the  flowers.     Perianth  an  inch 
and  a  half   across,    reddish  purple,   occasionally  white.      Filaments 
united  only  at  the  broad  base.     Style  merely  cleft  at  apex.     This  most 
beautiful  species  ranges  from  northern  California  to  British  Columbia. 

c.  S.  Calif or'nicum  Ait.    STAR-EYED  GRASS,  GOLDEN-EYED  GRASS. 
Scape  winged,  a  foot  or  more  high,  longer  than  the  leaves.     Flowers 


DICOTYLEDONOUS   PLANTS  39 

from  3  to  7,  yellow,  nearly  an  inch  in  diameter.  Spathe  1.  Filaments 
united  at  base  only.  Style  divided  to  the  middle.  Capsule  oblong. 
This  stains  the  paper  purple  when  it  is  pressed.  It  grows  in  swampy 
places  near  the  ocean. 

ORCHIDAXCE^.     ORCHIS  FAMILY 

Perennials,  with,  perfect  flowers  of  peculiar  shapes,  perianth 
of  6  divisions  adnate  to  the  1-celled  ovary,  which  contains  an 
immense  number  of  ovules.  The  stamens  are  1  or  2,  united 
with  the  pistil.  The  pollen  is  of  a  few  waxy  grains,  held 
together  by  cobweb-like  threads.  The  family  is  difficult,  and 
the  specimens  are  so  rare  that  they  should  not  be  collected  in 
large  numbers  for  class  study.  The  most  familiar  genera  are 
Cypifap^dium,  Lady's  Slipper  ;  Spiran'thes,  Ladies'  Tresses ; 
Epipac'tis. 


SUBCLASS   II.  —  DICOTYLEDONOUS   PLANTS 

Stems  composed  of  bark,  wood,  and  pith  ;  in  woody  stems 
which  live  over  from  year  to  year,  the  wood  is  generally  in 
annual  rings,  traversed  at  right  angles  by  medullary  rays. 
Leaves  netted-veined.  Cotyledons  2  (rarely  more). 

DIVISION  I 

APETALOUS  PLANTS.  FLOWERS  WITHOUT  A  COKOLLA,  OFTEN 
WITHOUT  A  CALYX.  CALYX  OFTEN  COLORED  LIKE  A 
COROLLA. 

PIPERA'CE^.     YERBA  MANSA  FAMILY 

Perennial  herbs  with  jointed  or  scape-like  stems.  Leaves 
entire,  with  petioles  dilated  at  base,  and  without  stipules. 
Flowers  perfect,  without  perianth,  in  dense  terminal  spikes, 
with  a  bract  under  each  flower.  Stigmas  1-5,  stamens  3-6 
or  more. 


40  KEY   AND   FLORA 


HOUTTUY'NIA  ( ANEMOP'SIS) ,  Yerba  Mansa 

Herbs  with  aromatic,  creeping  rootstocks,  and  most  of  the 
leaves  radical.  Flowers  in  spikes,  subtended  by  a  corolla-like 
involucre  on  a  few-leaved  stem.  Sepals  and  petals  none,  a 
petal-like  bract  under  each  flower.  Stamens  on  the  base  of 
the  ovary.  Ovaries,  sunk  in  the  fleshy  axis  of  the  spike,  each 
consisting  of  several  follicles,  which  open  and  appear  to  form 
a  1-celled  pod  with  several  parietal  placentae  ;  when  ripe, 
opening  at  the  apex,  leaving  the  old  spikes  full  of  regularly 
arranged  holes. 

H.  Califor'nica  Benth.  &  Hook.  YERBA  MANSA.  This  grows  in 
saline  or  alkaline  swamps,  and  has  reputed  medicinal  value. 


MYRICA'CE^.     WAX-MYRTLE  FAMILY       ^fAfr 

Monoecious  or  dioecious  trees  or  shrubs.  Leavesiragrant, 
alternate.  Flowers  in  short  sessile  catkins  with  one  naked 
flower  under  each  scale.  Staminate  flowers  of  about  10 
stamens  with  united  filaments.  Ovary  1-celled,  1-ovuled, 
with  2  sessile  thread-like  stigmas.  Fruit  a  small,  round, 
dark  purple  nut,  unevenly  coated  on  the  rough  surface  with 
grayish  white  wax. 

Myri'ca  Califor'nica  Cham.  Flowers  usually  androgynous.  Leaves 
evergreen,  leathery,  oblanceolate,  dark  green  and  glossy  above,  some- 
what whitened  below,  serrate  above  the  base,  and  narrowed  to  a 
short  petiole.  Catkins  solitary  or  in  thick  clusters.  From  Monterey 
to  Washington  in  moist  places. 


SALICA'CE.32.     WILLOW  FAMILY 

Dioecious  trees  or  shrubs.  Flowers  in  catkins  (/.  Fig.  131  ; 
K.  Figs.  108,  121),  destitute  of  perianth.  Fruit  a  1-celled  pod 
with  numerous  seeds,  provided  with  rather  long  and  silky 
down  (usually  called  cotton),  by  means  of  which  they  are 
transported  by  the  wind. 


DICOTYLEDONOUS  PLANTS  41 


I.     SA'LIX,  Willow 

Trees  or  shrubs,  growing  near  water.  Leaves  generally 
long  and  pointed  ;  with  stipules  generally  present  on  young 
shoots,  disappearing  from  the  older  leaves.  Stamens  1-6  to 
each  scale  of  the  staminate  catkin.  On  the  pistillate  catkin 
the  pods  are  small,  ovate,  pointed,  splitting  from  the  top  into 
two  pieces.  In  bud  the  catkins  are  covered  with  scales  that 
fall  off.  (The  following  species  generally  occur  as  trees, 
sometimes  also  as  shrubs.) 

«.  S.  ni'gra  Marsh.  BLACK  WILLOW.  Trunk  nearly  black,  gen- 
erally leaning  over  the  water.  Leaves  narrowly  lanceolate,  long-pointed, 
closely  serrate,  smooth  and  light  green  on  both  sides.  .Catkins  on 
leafy  branchlets.  Pods  brownish  on  short  pedicels.  Stamens  3-5  to 
each  scale.  Along  the  San  Joaquin  and  Sacramento  Rivers. 

b.  Si^gBviga'ta  Bebb.     Trunk  straight,  with  dark  brown  bark.    Leaves 
rather  truck,  glossy  green  above,  glaucous  beneath.     Scales  of  the 
catkin  toothed.     Otherwise  much  like  the  preceding,  but  with  broader 
leaves.     Widely  distributed. 

c.  S.  lasiol'epis  Benth.     Trunk  generally  straight,  with  grayish 
brown  bark,  almost  smooth.     Leaves  thick,  oblanceolate,  unequally 
serrate,  glaucous  and    brown-hairy  beneath.      The  young  leaves  are 
closely  covered  with  silky  hairs.      Catkins  on  very  short  peduncles  ; 
scales  dark  brown,  densely  covered  with  white  hairs.     Stamens  2  to 
each  scale,  with  the  Jilaments  united  at  the  base.     Pods  on  short  pedicels. 
This  is  the  most  common  willow  and  varies  considerably.     Widely 
distributed. 

d.  S.  Scouleria'na  Barratt  (S.  flaves'cens  Nutt.).  Small  tree  or  shrub. 
Leaves  silky  tomentose  on  the  underside  when  young,  obovate  or 
oblanceolate.     Catkins  short,  sessile,  appearing  before  the  leaves,  densely 
flowered.     Stamens  2  to  each  scale  of  the  catkin ;  scales  covered  with 
long  silky  hairs.      Capsules  tomentose  on   short  pedicels.     Styles 
wanting ;  stigmas  long,  entire  or  deeply  parted.    The  freshly  broken 
twigs  of  this  species  have  a  strong  and  disagreeable  odor.     It  is  one 
of.  the  earliest  willows  in  bloom  and  is  very  lovely  and  conspicuous 
when  in  bloom.     It  is  found  from  Santa  Barbara  to  Alaska. 

e.  S.  Sitchen'sis  Sanson.     Similar  to  the  above  but  with  leaves 
much   more   tomentose,    with  permanent   and   shining   tomentum. 
Catkins  long,  appearing  before  the  leaves  but  often  in  the  axils  of  the 
previous  season's  persistent  leaves.     Stamens  1-2  to  each  scale  of  the 
catkin;  scales  villous  and  catkins  tomentose.      This  is  a  beautiful 
willow  with  large  broad  leaves.     It  is  found  from  Santa  Barbara  to 
Alaska. 


42  KEY   AND   FLORA 

/.  S.  corda'ta  Muhl.  Small  tree  or  shrub.  Leaves  oblong  lanceo- 
late, heart-shaped  or  acute  at  base,  pointed  at  apex,  serrate,  smooth 
except  when  young.  Catkins  leafy  at  base,  cylindrical,  lengthening  in 
fruit.  Stamens  2  to  each  scale  of  the  catkin.  Scales  dark  but  villous 
with  long  white  hairs.  Capsule  smooth.  Style  short,  stigma  bifid. 
This  is  found  on  the  eastern  slope  of  the  Sierra  Nevada  Mountains. 
Northward. 

g.  S.  fluvia'tilis  (S.  longifolia).  NARROW-LEAVED  WILLOW. 
A  shrub  forming  dense  clumps.  Leaves  linear  to  lanceolate,  tapering 
at  apex  and  base,  sessile,  2-4  in.  long  and  ^  in.  or  less  wide ;  margin 
entire  or  with  scattered  teeth.  Catkins  on  leafy  branchlets.  Stamens 
2  to  each  scale.  Capsules  downy  or  smooth,  on  short  pedicels,  with 
large,  sessile  stigmas.  Sometimes  the  leaves  are  smooth,  sometimes 
white  downy.  This  is  widely  distributed  and  variable. 

II.     POP'ULUS,  Cottonwood,  Poplar,  Aspen 

Trees  with  broad  ovate  or  deltoid  leaves,  and  buds  covered 
with  scales  full  of  aromatic  balsam.  Staminate  catkins 
appearing  before  the  leaves,  with  many  stamens  to  each  scale, 
on  a  cup-shaped  disk  ;  anthers  purple,  staining  the  ground 
where  they  fall.  Fertile  catkins  of  round  or  ovate  pods  on 
slender  pedicels. 

a.  P.  trichocar'pa  Torr.     BALM    OF    GILEAD,    BALSAM    COTTON- 
WOOD.     Leaves  ovate,  pointed,  cordate  or  rounded  at  base,  crenate,  dark 
green  above,  greenish  brown  beneath,  on  terete  petioles.     Buds  full  of 
balsam,  and  very  fragrant.     Tree  with  cracked  bark  and  open  growth. 
Widely  distributed. 

b.  P.  Fremon'ti  Watson.    Leaves  broadly  deltoid,  with  few  rounded 
teeth  on  the  margins,  bright  green  on  both  sides;  petioles  flattened. 
Large  tree,  with  gray,  cracked  bark.     Widely  distributed. 

c.  P.  tremuloi'des  Michx.    ASPEN,  QUAKING  ASP.    Trunk  straight, 
slender,  with  smooth  grayish  white  bark.     Leaves  round-ovate,  thin, 
on  slender  petioles  flattened  at  right  angles  to  the  broad  surfaces  of  the 
leaf,  causing  it  to  sway  edgewise  with  the  least  perceptible  breeze.     In  the 
Sierra  Nevada  Mountains  and  far  northward. 


BETULAXCE^E.     BIRCH  AND  ALDER  FAMILY 

Monoecious  trees  or  shrubs,  growing  along  streams.  Leaves 
toothed.  Staminate  catkins  drooping  ;  when  young  covered 
with  resin,  but  without  bud-scales.  Stamens  2-4  in  a  4-lobed 


DICOTYLEDONOUS  PLANTS  43 

or  scale-like  perianth  under  the  bracts  of  the  catkin.  Pistil- 
late flowers  in  short,  erect  cones.  Pistil  with  a  2-celled  ovary 
and  2  stigmas. 

I.     AI/NUS,  Alder 

Trees  or  shrubs  with  broad,  toothed  leaves.  Staminate 
catkins  long  and  drooping,  appearing  in  early  spring.  Pistil- 
late catkins  erect,  becoming  dark  brown  and  woody,  persisting 
on  the  trees  for  some  time  after  the  seeds  have  fallen.  Stamens 
generally  4  in  each  perianth. 

a.  A.   rhombifo'lia  Nutt.       Trees  with  dark  brown  bark.      Leaves 
ovate    or  oval,   paler  beneath,    irregularly   glandular-toothed.      This 
blooms   very   early,    the    staminate    catkins  falling  in  January  or 
February,  and  the  fruit  ripe  at  the  same  time.     Widely  distributed. 

b.  A.    rub'ra   Bong  (A.  Orego'na   Nutt).     Bark  pale  gray,  mottled 
with  darker  gray.     Leaves    ovate    or  elliptical,   rusty-pubescent   on 
the  lower  surface,  doubly  serrate,  with  revolute  margins  to  the  teeth. 
Twigs  smooth,  winter  buds  glutinous,  nearly  £  in.  long.     Catkins 
open  in  the  spring  before  the  leaves.    From  San  Francisco  to  Alaska. 

c.  A.  tenuifolia  Nutt.     A  small  tree  with  red-brown  bark,  often 
forming  thickets.     Twigs  pubescent.     Leaves  ovate  rounded  or  cor- 
date at  base,  doubly  serrate  with  teeth  acute,  veins  prominent,  winter 
buds  short,   obtuse,   pubescent,  about  ^  in.  long.      In  the   Sierra 
Nevada  Mountains  and  northward,  especially  on  the  eastern  slope  of 
the  mountains. 

II.     BET'ULA,  Birch 

Trees  or  shrubs  with  smooth  bark  often  coming  off  in 
sheets,  dotted  on  the  branches.  Catkins  similar  to  those  of 
ALNUS,  but  the  fertile  ones  do  not  persist  on  the  trees  after  the 
seeds  are  ripe.  The  scales  and  seeds  fall  away  from  the  axis. 
Each  scale  of  the  staminate  catkins  bears  3  flowers,  each  of 
which  consists  mainly  of  two  2-parted  filaments  with  an 
anther  cell  on  each.  On  every  scale  of  the  pistillate  catkins 
are  borne  2-3  flowers,  each  of  which  consists  simply  of  a 
naked  ovary  with  2  diverging  stigmas. 

B.  occidenta'lis.  BLACK  BIRCH.  A  tree  20-30  ft.  high  with 
smooth  dark  brown  or  reddish  bark,  with  conspicuous  whitish  hori- 
zontal lenticels,  becoming  lighter  in  color  with  age  ;  the  branchlets 
dotted  with  resinous  spots.  Leaves  thin,  broadly  ovate,  serrate  with 


44  KEY   AND   FLORA 

glandular  teeth.  Seeds  with  wings  as  broad  as  the  body.  Bracts  of 
the  catkin  3-lobed.  Most  common  on  the  western  side  of  the  Rocky 
Mountains. 


CUPULIF'ER^.     OAK  FAMILY 

Monoecious  trees  or  shrubs.  Staminate  flowers  in  catkins  ; 
pistillate  forming,  in  fruit,  a  nut  in  a  cup-like  or  bur-like 
involucre.  - 

I.     QUER'CUS,  Oak 

Staminate  flowers  in  slender,  fringe-like  catkins,  with  a 
6-lobed  perianth  ;  pistillate  usually  single,  consisting  of  a 
3-celled  ovary  enclosed  in  a  bud-like  involucre  which  becomes 
a  cup.  Stigmas  3.  Only  1  of  the  ovules  ripens  to  form  an 
acorn  ;  the  other  5  can  be  seen  as  rudiments. 

a.  Q.  loba'ta  Nee.     VALLEY  OAK,  ROBLE,  WHITE  OAK,  WEEPING 
OAK.     Leaves  large,  deciduous,  deeply  lobed  with  obtuse  divisions, 
3-4  in.  long  on  stout  petioles.     Cup  deep,  with  a  rough  warty  sur- 
face, acorns  1—3  in.   long,  usually  pointed.      These  trees  grow   to  a 
great  size,  and  are  generally  isolated  in  fertile  valleys.     They  have 
graceful,  drooping  branches.     Throughout  California. 

b.  Q.  Garrya'na  Dougl.     A  large  tree,  often  10-12  ft.  in  circumfer- 
ence, with  bark  only  1  or,  at  most,  2  in.  thick.    Leaves' thick,  strongly 
veined,  4-6  in.  long,  2-5  in.  wide,  with  coarse  lobes,  obtuse  or  acute, 
entire  or  again  lobed,  dull  green   on  the  upper  side,  pale   green   or 
yellowish  on  the  lower,  turning  brown  or  red  in  the  fall. .    Acorns 
sessile  or  on  short  peduncles,  with  the  nut  oval  and  obtuse,  about  1 1 
in.  long,  in  small,  shallow  cups.     The  winter  buds  of  this  oak  are 
nearly  half  an  inch  long  and  are  densely  tomentose.    It  is  found  in  the 
valleys  and  hills  north  of  San  Francisco  Bay  and  extends  to  British 
Columbia.    It  is  common  in  Oregon  and  Washington. 

c.  Q.  Douglas'ii  Hook.  &  Arn.     BLUE  OAK,  WHITE  OAK.     Leaves 
an  inch  or  two  long,  deciduous,  oblong,  with  shallow  lobes,  bluish 
green,  veiny.      Cup  usually  shallow,  with  flat  scales ;    acorns  oblong, 
often  swollen  in  the  middle.     Bark  usually  light  gray,  causing  the 
trunks  to  be  very  noticeable  on  hillsides.     From  Tehachapi  to  the 
Sacramento  Valley. 

d.  Q.  oblongifo'lia  Torr.     EVERGREEN  LIVE  OAK  or  WHITE  OAK 
of  southern  California.    Leaves  evergreen,  oblong,  often  entire,  or  with 
a  few  blunt  teeth,  thick,  with  the  veining  almost  concealed.     Cup  with 
warty  surface,  acorns  oblong.     Not  found  north  of  Tehachapi. 


DICOTYLEDONOUS  PLANTS  45 

e.  Q.  chrysol'epis  Liebm.  DROOPING  LIVE  OAK,  GOLDEN  CUP 
OAK.  Leaves  evergreen,  oblong,  entire  or  spinosely  toothed,  often 
both  kinds  on  the  same  branch,  dark  green  on  the  upper  surface,  cov- 
ered with  a  golden  powder  on  the  lower  surface  of  young  leaves :  the  old 
leaves  becoming  smooth  and  paler  beneath.  Cup  either  bowl  or  saucer 
shaped,  more  or  less  covered  with  yellow  powder,  sometimes  so  dense 
as  to  conceal  the  scales  of  the  cup.  Acorns  large  and  thick.  This 
is  a  shrub  or  an  immense  tree  growing  usually  in  canons.  It  is 
extremely  variable  in  leaves  and  fruit.  Throughout  California. 

/.  Q.  agrifolia  Nee.  LIVE  OAK,  ENCINO.  Leaves  evergreen, 
spiny-toothed  on  the  margin,  which  is  curled  under.  Pubescence  stellate. 
Staminate  flowers  very  numerous.  Cup  bowl-shaped,  glossy,  of  flat 
scales ;  acorns  slender,  tapering,  maturing  in  one  year.  This  is  a 
round,  compact  tree,  or  it  sprawls  over  the  ground  with  low  branches, 
widely  spreading.  This  never  grows  far  from  the  sea,  but  keeps 
within  the  fog-line. 

g.  Q.  Wislize'ni  A.  DC.  POST  OAK,  LIVE  OAK.  Leaves  ever- 
green, dark,  glossy,  spiny-toothed,  but  not  curled  back,  very  stiff, 
smooth  on  both  sides  when  old.  Acorns  maturing  in  2  years.  Cup  deep, 
very  rough-scaly.  Acorns  variable,  often  almost  covered  by  the  cup. 
This  is  usually  a  tree,  but  is  often  shrubby  and  is  found  throughout 
California. 

h.  Q.  Califor'nica  Cooper  (Q.  Kelloggii).  KELLOGG'S  OAK,  BLACK 
OAK.  Leaves  deciduous,  large,  deeply  lobed  with  pointed  divisions, 
smooth  and  glossy  green  when  old.  Fruit  on  short  stems.  Cups 
deep  with  smooth  scales  ;  acorns  large,  oblong,  obtuse.  Bark  black 
and  rough.  The  young  shoots  are  rose-color  and  densely  tomentose. 
Through  the  mountains  of  California. 

i.  Q.  densiflo'ra  Hook  &  Arn.  CHESTNUT  OAK,  TANBAKK  OAK. 
Leaves  evergreen,  oblong,  ribbed  with  thick  veins,  toothed,  covered  more  or 
less  with  white  tomentum.  Cups  saucer-shaped,  densely  covered  with 
long,  linear,  curved  scales  that  give  the  cup  a  bristly  appearance  ; 
acorns  large,  with  a  thick  shell.  This  is  in  flower  and  fruit  at  the 
same  time,  generally  blooms  in  summer,  and  has  large panicled  spikes 
of  androgynous  Jlowers.  From  the  Tehachapi  Range  northward. 


II.     CASTANOP'SIS,  Western  Chinquapin 

Flowers  androgynous  in  erect  axillary  or  terminal  panicled 
spikes.  Staminate  flowers  with  perianth  5-6-lobed,  and 
stamens  twice  as  many  ;  sessile  on  the  upper  part  of  the 
spikes.  Pistillate  flowers  below,  in  a  scaly  involucre.  Ovary 
3-celled,  with  2  ovules  in  each  cell,  maturing  only  1—3  nuts  in 
a  roundish  involucre,  densely  covered  with  brown,  intricately 


46  KEY    AND   FLORA 

branched  prickles.     This  blooms  chiefly  in  the   summer  and 
fall,  and  is  generally  fruiting  at  the  same  time. 

a.  C.  chrysophylla  A.  DC.    GOLDEN-LEAVED  CHINQUAPIN.    Leaves 
lanceolate,  pointed,  dark  green  above,  golden  below.     This  is  generally 
a  shrub,  but  becomes  a  large  beautiful  tree  in  Mendocino  County. 

b.  C.  semper'virens  Dudley.     Leaves  obovate-oblong,  obtuse  at  apex. 
This  is  the  species  of  the  Sierra  Nevada  Mountains. 

III.     COR'YLUS,  Hazelnut 

Staminate  flowers  in  slender,  drooping  catkins,  each  flower 
consisting  of  8  stamens  with  1-celled  anthers.  Pistillate 
flowers  several,  grouped  in  a  scaly  bud,  each  consisting  of  a 
single  ovary  in  the  axil  of  a  bract,  and  with  a  smaller  bract 
on  each  side.  Ovary  2-celled,  2-ovuled  (one  seed  only  matur- 
ing). Stigmas  2,  bright  red,  long  and  slender.  Nut  roundish, 
enclosed  in  a  fringed  cup. 

C.  rostra'ta  Ait.  var.  Califor'nica  A.  DC.  Shrubby.  Leaves  slightly 
heart-shaped.  Staminate  flowers  drooping,  very  numerous;  con- 
spicuous on  the  leafless  stems  of  winter.  Involucre  completely 
covering  the  nut,  and  prolonged  into  a  beak  above  it.  This  is 
common  in  the  woods  along  the  coast.  It  blooms  very  early. 


ARISTOLOCHIA'CE^:.     DUTCHMAN'S  PIPE  FAMILY 

Shrubs  or  perennial  herbs.  Leaves  heart  or  kidney  shaped, 
palmately  veined.  Perianth  adnate  to  the  6-celled  ovary, 
greenish  brown,  regular  or  irregular.  Stamens  6-1 2,  attached 
to  the  style,  with  anthers  opening  outwards.  Styles  6,  united 
at  base. 

I.     AS' ARUM,  Wild  Ginger 

Low  herbs.  Leaves  and  flowers  springing  from  creeping  root- 
stocks  which  have  the  odor  of  ginger.  Leaves  large,  kidney- 
shaped,  on  long  petioles.  Flowers  erect,  bell-shaped,  with  3 
divisions  bearing  long  tails.  Stamens  12,  almost  free  from  the 
style.  Capsule  round.  Seeds  large,  2  rows  in  each  cell. 

a.  A.  cauda'tum  Lindl.  Flowers  on  slender  pedicels.  Divisions 
of  the  perianth  with  tails  from  1  to  3  in.  long.  This  grows  in  damp, 
shady  places  under  the  trees  in  the  Coast  Mountains. 


DICOTYLEDONOUS  PLANTS  47 

b.  A.  Hartwe'gi.  Flowers  on  stout  peduncles,  from  a  woody  base. 
Divisions  of  the  perianth  narrowed  to  a  linear  apex.  Leaves  marked 
with  lighter-colored  veins,  often  white-veined.  This  grows  in  the 
higher  parts  of  the  Sierra  Nevada  Mountains  under  the  trees. 

II.     ARISTOLO'CHIA,  Dutchman's  Pipe 

Perianth   something   like   a  pipe   in   shape,    inflated,    soon 
deciduous  from  the  inferior  ovary.     Anthers  6,  sessile,  adnate 
to  the  short  style.     Stigmas  3-6-lobed.     Pod  club-shaped. 
A 

AX5alifor/nica  Torr.  A  shrubby  vine  with  twining  stems.  Flowers 
greenish  brown  with  purplish  brown  stripes  and  markings,  appearing 
before  or  with  the  leaves,  in  the  leaf  axils.  Peduncles  slender,  with 
a  leaf-like  bract  in  the  middle.  Leaves  soft,  pubescent,  ovate-cordate 
on  short  petioles.  This  climbs  amid  the  brush,  from  which  it  is  not 
readily  distinguishable,  as  the  colors  of  the  flower  are  so  similar  to 
its  surroundings,  and  usually  there  are  no  leaves  when  the  flowers 
are  in  bloom. 


POLYGON  A'CE-ZE.     BUCKWHEAT  FAMILY 

Shrubs  or  herbs.  Perianth  small,  generally  corolla-like,  of 
3-6  distinct  or  united  divisions.  Stamens  4-9  on  the  perianth. 
Ovary  a  3-sided  or  lens-shaped  akene,  generally  dark  brown 
or  black.  Styles  2-4. 

I.     ERIOG'ONUM,  California  Buckwheat 

Flowers  small,  perfect,  on  hair-like  pedicels  from  bell-shaped 
or  top-shaped  involucres.  Perianth  of  6  petal-like  divisions, 
thin  in  texture,  yellow,  white,  or  rose-color.  Stamens  9. 
Styles  3,  generally  deflexed  or  curled,  with  cap-like  stigmas. 
Akenes  3-sided  (rarely  lens-shaped  or  winged).  Leaves  without 
sheaths  or  stipules,  often  more  or  less  white-woolly,  generally 
in  a  spreading  cluster  at  the  base  of  the  stem.  The  smail 
involucres  full  of  flowers  are  variously  clustered  in  umbels, 
panicles,  racemes,  etc. 

These  plants  inhabit  dry  places.  The  species  are  very 
numerous,  and  difficult  to  distinguish.  The  majority  of  the 
species  are  annuals,  much  branched,  with  slender  stems.  The 
perennial  species  are  stouter,  and  one,  E.  fascicula'tum,  is  an 


48  KEY   AND   FLORA 

evergreen  shrub,  with  small,  short  leaves  in  clusters  along  the 
stems,  and  the  flowers  in  terminal  cymose  panicles. 

H.     CHORIZAN'THE,  Turkish  Rugging 

Involucres  sessile,  tubular,  thick  in  texture,  3-6-ribbed,  with 
as  many  teeth  or  divisions,  tipped  with  stiff  bristles.  Flowers 
small,  1-3,  included  in  the  involucres,  often  nearly  sessile. 
Stamens  generally  9.  Ovary  smooth  and  akene  triangular. 
Low,  much  branched  annual  herbs  with  slender  branches,  very 
brittle  when  dry.  The  leaves  are  all  in  a  cluster  at  the  base, 
and  the  bracts  are  ternate  and  usually  small.  They  grow  in 
dry,  sandy  places,  where  they  often  cover  the  ground  as  with 
a  veil.  The  species  are  numerous,  generally  local  and  difficult 
to  distinguish. 

IH.     RUMEX,  Dock,  Sorrel 

Coarse  herbs,  generally  perennial,  with  acid  or  bitter  juice. 
Perianth  with  3  outer  divisions  green,  the  3  inner  generally 
larger,  reddish  or  yellowish  green,  becoming  large  and 
often  with  a  white  grain  on  the  back  of  one  or  all  of  the 
divisions,  which  closely  cover  the  3-sided  akene.  Styles  3. 
Stigmas  with  a  tuft  of  hairs  at  the  top.  Leaves  with  papery 
stipules  sheathing  the  stem. 

a.  R.  acetosella  L.      SORREL,   SOUR  GRASS.      Flowers  dioecious, 
small,  in  a  narrow  panicle,  becoming  reddish.     The  inner  divisions 
of  the  perianth  do  not  enlarge  over  the  akene.     Leaves  thick,  hastate. 
This  is  very  common,  spreading  by  slender  rootstocks.     The  male 
plants  greatly  exceed  the  female  in  number.    Common  everywhere. 

b.  R.  salicifolius  Wein.     WILLOW-LEAVED  DOCK.     Stems  several, 
generally  spreading  and  ascending  or  erect.    Leaves  light  green,  3-6 
in.  long,  lanceolate,  narrowed  to  a  short  petiole.     Flowers  in  a  leafy 
panicle,  which  becomes  dark  red  as  it  grows  old.     Each  of  the  inner 
divisions  of  the  perianth  has  a  large  grain  on  the  outside.     Common  in 
moist  places  everywhere. 

c.  R.  cris'pus  L.     CURLY  DOCK.     Leaves  on  long  stalks  with  a 
crisped  or  curled  margin.     Flowers  in  a  leafy  panicle.      The  grains 
are  present  on  all  the  inner  divisions  of  the  perianth.     Common. 

d.  R.  purcher  L.     Branches  widely  spreading,  leafy,  reddish  when 
young,   becoming   brown    and   stiff   when   old.     Leaves   rough  on 
the   lower   surface,    generally   lanceolate    and   acute.      Flowers   in 


DICOTYLEDONOUS   PLANTS  49 

numerous  whorls  at  short  intervals  along  the  branches.  Perianth 
with  the  inner  divisions  all  grain-bearing  and  with  J^-6  stiff  bristly  teeth 
on  each  side.  This  is  an  introduced  weed,  becoming  very  common. 

e.  R.  occidentals  Watson.  Tall,  3-6  ft.  in  height.  Lowest  leaves 
with  blade  often  a  foot  long  and  petiole  almost  as  long,  ovate  to 
oblong-lanceolate,  with  the  base  heart-shaped.  Panicle  large,  almost 
destitute  of  leaves.  Perianth  with  large  reddish  divisions,  finely 
toothed  near  the  cordate  base,  without  grains  on  the  back.  This  grows 
in  wet  places  throughout  the  Pacific  coast  and  blooms  in  summer. 

/.  R.  persicarioi'des  L.  Annual,  generally  with  many  stems, 
low,  erect,  or  spreading.  Leaves  linear-lanceolate,  on  short  petioles. 
Flowers  in  dense  whorls  at  nearly  all  the  leaf  axils.  Divisions  of  the 
perianth  all  bearing  grains  and  with  2-3  long,  slender,  awn-like  teeth 
on  each.  This  is  found  in  wet  places,  generally  along  the  edges  of 
ponds  and  lakes.  It  is  widely  distributed  and  blooms  in  summer. 

IV.     POLYG'ONUM,  Jointweed,  Smartweed 

Flowers  perfect  in  axillary  or  panicled  spikes.  Perianth 
of  5-6  petal-like  divisions,  often  rose-color,  not  enlarging  in 
fruit.  Stamens  4-9.  Styles  2-8,  with  cap-like  stigmas.  At 
the  base  of  the  petiole  there  are  papery  sheaths  around  the  stem. 
The  species  are  difficult  to  determine.  They  generally  grow 
in  swampy  places. 


CHENOPODIA'CEJE.     PIGWEED  FAMILY 

Shrubs  or  herbs,  often  with  fleshy  stems  and  leaves,  usually 
found  near  the  ocean  or  in  alkaline  soil,  often  covered  with 
white  scurf.  Leaves  generally  salty  or  bitterish.  Flowers 
perfect,  monoacious  or  dioecious.  Perianth  small,  of  5  greenish 
sepals.  Stamens  as  many  as  the  sepals,  and  opposite  them. 
Ovary  1-celled,  with  the  embryo  coiled  in  a  ring  or  spiral 
around  the  endosperm. 

I.     CHENOPO'DIUM 

Flowers  perfect  in  axillary  or  terminal  clusters.  Perianth 
nearly  covering  the  fruit,  which  is  round  and  flattened.  Leaves 
alternate  on  petioles,  often  covered  with  scurf  or  down. 


50  KEY  AND  FLORA 

a.  C.  arbum  L.      LAMB'S-QUARTER,   PIGWEED.     Annual,  erect, 
simple  or  branched.     Leaves  cold  to  the  touch,  covered  with  a  /lour- 
like  powder,  from  lanceolate  to  ovate,  wavy  and  toothed.     Flowers 
in  spikes,  either  simple  or  panicled,  and  axillary  or  terminal.     This 
is  common  in  cultivated  ground. 

b.  C.  Califor'nicum  Watson.     SOAP    PLANT.      Perennial,   from   a 
spindle-shaped  root.     Steins  smooth,  usually  several  from  the  root, 
spreading  and  ascending.      Leaves  triangular,  2-3  in.  long,  sharply 
and  irregularly  toothed.     Flowers  densely  clustered  in  long,  slender, 
terminal  spikes.      Seed  large,  vertical,  only  partly  covered  by  the 
5-toothed,  bell-shaped  perianth.    This  blooms  in  spring,  often  under 
bushes.     Near  the  coast,  from  San  Diego  to  San  Francisco  Bav. 

c.  C.  mura'le  L.     Stems  generally  reddish,  with   some  flour-like 
powder,  branching  rather  closely,  forming  a  compact  plant,  a  foot  or 
two  high.     Leaves  broadly  triangular  to  lanceolate,  coarsely  and  deeply 
sinuate-toothed.     Flowers  generally  in  small  clusters  in  the  leaf  axils, 
shorter  than  the  leaves.     Sometimes  the  clusters  are  panicled  at  the 
top  of  the  stems.     Seeds  black  with  sharp  edges.     Common  every- 
where. 

d.  C.  ambrosioi'des  L.     WORMSEED.     Stems  annual,  stout,  and 
branching,  2-3  ft.  high.     Leaves  lance-shaped,  2-5  in.  long,  sinuate- 
dentaie,  on  short  petioles.     Flowers  in  axillary  spikes,  or  in  panicled 
leafless  spikes.     The  entire  plant  has  a   strong,  persistent,  aromatic 
odor.     It  is  common  in  salt  and  alkaline  marshes. 


II.     AT'RIPLEX,  Salty  Sage 

Herbs  or  shrubs,  mealy,  scurfy  or  pubescent.  Flowers  in 
simple  or  panicled  spikes,  or  clustered  in  the  axils.  Staminate 
flowers  with  the  divisions  of  the  perianth  3-5,  and  stamens 
opposite  the  divisions.  Pistillate  flowers  enclosed  by  2  bracts, 
which  are  distinct  or  united,  variously  toothed,  or  with  wart- 
like  protuberances  or  winged,  often  thickened.  Seed  vertical, 
generally  falling  with  the  bracts  which  enclose  it. 

a.  A.  Califor'nica  Moquin.     Stems  many  from  the  base,  spreading 
on  the  ground  a  foot  or  more,  densely  mealy.     Leaves  sessile,  small, 
lanceolate,  the  lower  opposite.     Flowers  monoecious  in  small,  axillary 
clusters,   the   staminate   ones  mostly  near    the    top  of  the  cluster. 
Fruiting  bracts  small,  round,  spongy,  not  toothed,  and  without  wart-like 
protuberances.     This  is  found  along  the  coast. 

b.  C.  canes'cens    James.       BUCKWHEAT     SAGE,     SALTY     SAGE. 
Shrubby,  dioecious.     Leaves  grayish  green,  linear  or  oblanceolate. 
Flowers  in  panicled    spikes.     Fruiting  bracts  with  4  distinct  dilated 


DICOTYLEDONOUS   PLANTS  51 

wings.     This  is  found  in  the  interior,  in  alkaline  valleys.     It  is  a 
valuable  forage  plant. 

(The  species  of  Atriplex  are  numerous  and  difficult,  also 
somewhat  local,  so  the  rest  will  be  omitted.) 


AMARANTA'CE^J.     AMARANTH  FAMILY 

Herbs,  with  small  papery  flowers  surrounded  with  persist- 
ent papery  bracts.  Perianth  persistent  of  from  1  to  5  papery 
divisions.  Stamens  as  many  as  the  divisions  of  the  perianth, 
sometimes  fewer.  Ovary  1-celled  and  1-seeded,  forming  a 
fruit,  which  opens  like  the  lid  of  a  box.  Seed  always  ver- 
tical. Stigmas  2-3,  sessile. 

AMARAN'TUS.     Amaranth 

Flowers  generally  monoecious.  Perianth  of  from  3  to  5 
divisions.  Bracts  3  to  each  flower.  Stamens  with  filaments 
spreading  at  base.  Stigmas  generally  3,  forming  3  beaks  on 
the  fruit.  Seeds  brown  or  black,  dropping  readily  when  ripe. 

a.  A.  retroflex'us  L.     PIGWEED.     Stems  stout,  erect.    Leaves  ovate, 
1-3  in.  long,  on  petioles  almost  as  long.     Flowers  green,  in  thick, 
erect,  crowded  spikes,  either  terminal  or  axillary.     Divisions  of  the 
perianth  5.     A  common  weed. 

b.  A.    al'bus    L.     TUMBLEWEED.      Stems    light    green,    branching 
diffusely  from  the  base,  forming  a  mound-like  plant.     Leaves  spatulate 
or  obovate,  often  wavy-margined,  on  slender  petioles.     Divisions  of 
the  perianth  3,  pointed,  shorter  than  the  fruit.     Bracts  awl-shaped 
with  stiff  points.    This  forms  a  tumbleweed,  and  will  often  be  found 
caught  in  fences  and  bushes.     Common  everywhere. 


NYCTAGINA'CE.32.     FOUR-O'CLOCK  FAMILY 

Herbs  with  fragile  stems  and  swollen  joints.  Leaves 
opposite,  entire,  unequal  at  base.  Flowers  perfect,  several 
in  an  involucre  resembling  a  calyx.  Perianth  corolla-like, 
showy,  the  base  hardening  around  the  1-seeded  ovary. 


52  KEY  AND   FLORA 


I.     MIRAB'ILIS,  Four-o'clock 

Involucre  5-lobed.  Flowers  nearly  sessile.  Stamens  5. 
Fruit  scarcely  ribbed.  Herbs  with  showy,  reddish  purple 
flowers,  opening  in  the  afternoon. 

a.  M.  multiflo'ra  Gray.     Stems  often  glandular;  stout  and  spread- 
ing.    Leaves  broad,  an  inch  or  two  long,  ovate,  on  petioles  a  half- 
inch  long.     Flowers  6  in  the  involucre.     Perianth  open-funnel-form, 
with  border  an  inch  in  diameter,  and  tube  from  1   to  2  in.  long. 
Southern  California. 

b.  M.  Califor'nica  Gray.     Stems  several  from  a  woody  root,  sup- 
ported on  bushes,  as  if  climbing.     Leaves  ovate,  cordate,  on  short 
petioles.     Involucre  small,  1— 3-flowered.     Perianth  open-bell-shaped. 
Fruit  small.     This  is  common  in  southern  California. 


H.     ABRO'NIA,  Sea  Verbena 

Involucre  of  from  5  to  15  distinct  papery  bracts.  Flowers 
sessile,  with  salver-shaped  perianth,  having  a  long  tube,  and 
the  border  with  notched  segments.  Stamens  5,  within  the 
tube.  Annual  or  perennial,  fleshy  herbs,  with  thick,  opposite 
leaves.  Flowers  in  umbels  on  long  peduncles,  fragrant,  showy, 
rose-color,  yellow,  or  white. 

a.  A.  umbella'ta  Lam.     Stems  prostrate,  viscid.     Leaves  ovate  or 
oblong,  narrowed  at  base  to  a  petiole.     Perianth  rose-color.     Fruit 
winged.     This  grows  on  the  seacoast. 

b.  A.  latifo'lia  Esch.     Steins  similar  to    above.     Leaves  broadly 
ovate,  with  kidney-shaped  base.     Perianth  yellow.     The  flowers  have 
the  odor  of  orange  blossoms.    This  is  found  on  the  coast  from  Van- 
couver to  Monterey. 


PORTULACA'CE-flS.     PORTULACA  FAMILY 

Fleshy  herbs.  Flowers  with  2  sepals  (except  in  Lewisia) 
and  2-5  or  more  petals.  Stamens  opposite  the  petals  when 
of  the  same  number.  Ovary  1-celled,  style  2-8  cleft.  The 
flowers  open  only  in  the  sunshine  or  bright  daylight. 


DICOTYLEDONOUS  PLANTS  53 


I.     PORTULA'CA,  Purslane 

Low  herbs  with  alternate  or  opposite  leaves.  Flowers  ter- 
minal and  sessile.  Petals  4-6.  Stamens  7-30,  inserted 
where  the  calyx  joins  the  ovary.  Pistils  with  3-8  styles. 
Fruit  like  a  box  opening  with  a  lid,  full  of  black  seeds. 

P.  olera'cea.  PURSLANE,  PUSLEY.  Prostrate.  Flowers  small. 
Calyx  lobes  keeled.  Petals  yellow,  spreading,  notched.  Common 
everywhere. 

n.     LEWIS1A,  Bitter-root 

Low  herbs,  without  stems,  from  thick,  perpendicular  roots. 
Leaves  forming  a  rosette  at  the  apex  of  the  root.  Flowers 
large,  solitary,  on  low  scapes,  conspicuous  when  open,  white  or 
rose-color.  Sepals  2-8.  Petals  3-16.  Stamens  numerous. 
Style  branches  3-8.  Pod  globose,  with  thin  walls  that  split 
from  the  base  upwards. 

L.  redivi'va.  BITTER-ROOT.  Leaves  numerous,  shorter  than  the 
scapes.  Scapes  jointed  above  the  middle,  bearing  an  involucre  of 
5-7  papery  bracts.  The  flower  when  expanded  is  an  inch  in  diam- 
eter, resembling  a  small  cactus  blossom.  The  sepals  resemble  the 
petals.  The  Bitter  Root  Mountains  receive  their  name  from  this 
plant.  It  is  the  state  flower  of  Montana. 


IH.     CALANDRIN'IA 

Sepals  green  and  persistent.  Petals  and  stamens  usually  5, 
the  former  sometimes  3-10,  the  latter  often  indefinite.  Ovary 
3-valved.  Seeds  black  and  shining  or  rough,  numerous. 

a.  C.  Menzie'sii  Torr.  &  Gray.     Flowers  crimson  or  magenta  in 
racemes.     Petals  a  little  longer  than  the  sepals.    Stamens  3-10.    Seeds 
shining.     Widely  distributed. 

b.  C.  el'egans  Spach.     Stems  rather  stout,  smooth,  with  ascending 
branches.     Flowers  numerous,  rose-color.     Petals  twice  as  long  as  the 
sepals.    Stamens  10-15.    Usually  found  most  abundant  in  cultivated 
ground. 

IV.     MON'TIA,  Miner's  Lettuce 

Petals  and  stamens  5.  Pod  3-valved  and  8-seeded.  Flowers 
white  or  rose-color,  in  racemes  or  panicles.  When  the  seeds 


54  KEY   AND   FLORA 

are  ripe  they  are  shot  out  of  the  pod  by  the  elastic  closing 
of  the  valves. 

a.  Jffi.  perfolia'ta  Howell.    MINER'S  LETTUCE.     Root  leaves  on  long 
petioles,  stem  leaves  forming  a  round  perfoliate  leaf  below  the  flowering 
stems.     Flowers   small,   white,    often   growing   on  but  one  side   of 
the  stem.     This  is  very  common  and  widely  distributed.     It  grows 
in  the  shade  and  blooms  in  spring  and  early  summer. 

b.  M.  Sibirlca  Howell.     Stems  brittle,  often  climbing  over  other 
vegetation  and   growing  in  swampy  places.     Leaves  sessile  but  not 
united.     Flowers  pink  or  white,  a  half  inch  in   diameter,  on  long 
pedicels,  in  long,   loose  racemes.      From  Marin    County  to  Alaska, 
blooming  in  spring  and  summer. 

c.  M.   gypsophiloi'des   Howell.     Annual,  pale   green,  with   many 
slender  stems  from  the  root,  3-10  in.  high.     Root  leaves  linear  or 
linear-spatulate,  shorter  than  the  stems.     Stem  leaves  at  the  base  q/ 
the  panicle  partly  united  on  one  side.     Flowers  numerous,  pink,  sweet- 
scented.     This  blooms  in  early  spring  and  grows  on  rocky  banks  and 
hills.     It  is  very  variable  in  size  and  shape  of  leaves.     In  the  coast 
mountains  of  central  California. 

d.  M.  linea'ris  Greene.     Annual,  6  in.  to  a  foot  high,  branching. 
Leaves   almost  thread-like,  fleshy,  an  inch   or   so    long,   becoming 
slightly  wider  toward  the  apex.     Flowers  in  racemes  on  one  side  of 
the  stem  on  pedicels  that  recurve  in  fruit.     Petals  white,  tinged  with 
pink,   unequal,    narrowed  at   base,    separate   or    somewhat    united. 
Moist  places  through  California  and  northward,  blooming  in  spring. 

e.  M.  Chamisso'nis   Greene.     Stems   erect  or  procumbent,  propa- 
gating by  runners  that  have  a  round  bulblet  at  the  tip.     Leaves  oblong- 
spatulate,  in  several  pairs.     Flowers  in  racemes,  the  bracts  present  only 
with  the  lower  flowers,  on  pedicels  that  recurve  in  fruit.     Petals  rose- 
color,  longer  than  the  calyx.     Seeds  kidney-shaped,  covered  all  over 
with  tubercles.     This  is  widely  distributed  and  grows  in  wet  places, 
blooming  in  spring  and  summer. 


V.     SPRA'GUEA,  Pussy-paws 

Sepals  thin  and  papery.  Petals  4.  Stamens  3.  Style  with 
2  lobes  at  the  apex.  Pod  2-valved.  Flowers  densely  clustered 
in  umbellate  spikes  curling  in  at  the  tips. 

S.  umbella'ta  Torr.  Stems  several,  usually  from  a  thick  root. 
Root  leaves  oblanceolate  or  spatulate,  forming  a  rosette  at  the  base, 
stem  leaves  becoming  mere  bracts.  Flowers  light  rose-color.  Common 
in  the  Sierra  Nevada  Mountains. 


DICOTYLEDONOUS  PLANTS  55 


CARYOPHYLLA'CE.®.     PINK  FAMILY 

Herbs  with  regular  flowers,  sepals  as  many  as  the  petals 
(generally  5,  the  latter  sometimes  wanting),  stamens  as 
many  or  twice  as  many,  ovary  l-celled  with  central  placenta, 
styles  2-5. 

I.     SILE'NE,  Pink 

Sepals  united  into  a  5-toothed  calyx.  Petals  with  both  blade 
and  claw,  together  with  the  10  stamens,  attached  to  the  stipe 
of  the  ovary.  Styles  3.  Capsule  dehiscent  from  the  top  by 
6  teeth.  Leaves  opposite,  without  stipules.  Flowers  gener- 
ally showy. 

a.  S.  Gal'lica  L.     Stems   generally  several.     Leaves  hairy,  spat- 
ulate.     Flowers  small,  on  short  pedicels  in  one-sided  racemes.     Petals 
pale  rose-color,  not  much  longer  than  the  sepals.     This  is  a  common 
introduced  weed. 

b.  S.  Califor'nica  Durand.     Low,  glandular  herbs,  with  lax,  leafy 
stems,  generally  branching  above.     Flowers  few,  nearly  an  inch  in 
diameter,  on  short  pedicels,  the  lowest  of  which  are  deflexed  in  fruit. 
Petals  5,  bright  scarlet,  the  blades  cut  into  2  divisions,  which  are,  gener- 
ally toothed.     Widely  distributed  in  shady  places  where  the  ground 
does  not  become  very  dry. 

c.  S.  lacinia'ta  Cav.      Stems   ascending,    1-2  ft.   high.      Leaves 
narrow,  2-3  in.  long.     Flowers  few  on  the  long  branches.     Blades 
of  the  petals  Deleft  into  linear  lobes,  scarlet,  smaller  than  the  preced- 
ing.    Pedicels  not  deflexed  in  fruit.     This  is  common  in  southern 
California. 

d.  S.   verecun'da   Watson.     Stems   several   from   the    rootstocks, 
branching,    leafy,    glandular-viscid,    especially   on   the   upper   part. 
Leaves  lanceolate,  spatulate  or  linear.     Flowers  1-3  at  the  ends  of 
short  branchlets.     Petals  with  blades  shorter  than  the  claws,  rose-color ; 
blades  2-cleft  and  with  the  appendages  in  the  throat  oblong,  entire  or 
toothed.    This  is  common  in  San  Francisco  near  the  cemeteries.     It 
is  widely  distributed  in  California. 


II.    CERASTIUM,  Mouse-ear  Chickweed 

Sepals  separate.      Petals  5,  white,   notched.      Stamens   10. 
Stigmas  5.     Capsule  dehiscent  from  the  top  by  10  teeth. 


56  KEY   AND   FLORA 

a.  C.   arven'se   L.      Perennial,    with    spreading    stems.      Leaves 
linear-lanceolate,  clasping  the  stem.     Flowers  ^  in.  in  diameter,  on 
long  pedicels,  in  few-flowered  cymes.      Capsule  extending  but  little 
beyond  the  calyx.     Common  around  San  Francisco  and  northward. 

b.  C.  visco'sum  L.     Annual,  somewhat  clammy,  branched  from 
the  base.     Leaves  small,  generally  ovate.    Flowers  on  short  pedicels 
in  rather  close  cymes.     Petals  shorter  than  the  calyx.      Capsule  nearly 
straight,  much  longer  than  the  calyx.     The  flowers  open  only  in  sun- 
shine.    This  is  an  introduced  weed. 

III.    STELLA'RIA,  Chickweed 

This  is  similar  to  Cerastium,  but  the  petals  are  2-lobed,  and 
the  capsule  is  globose,  dehiscent  to  below  the  middle. 

a.  S.  me'dia  L.     CHICKWEED.     Annual,  spreading  and   rooting 
at  the  lower  joints.     Leaves  ovate,  petioled.     Flowers  small,  on  slen- 
der pedicels,  which  are  deflexed  in  fruit,  in  the  axils  of  leafy  bracts. 
Stamens  3-10.     Pod  equaling   or   surpassing   the   calyx.     This  is 
introduced,  and  is  very  common  in  shady,  damp  places. 

b.  S.  ni'tens   Nutt.     Animal,   low,   with  slender,   shining    stems. 
Flowers   small,  erect,  on  short   pedicels.     Sepals  shining,  3-nerved, 
twice  as  long  as  the  petals,  which  are  sometimes  wanting.     Pod  shorter 
than  the  calyx.     This  is  a  delicate  little  plant,  with  inconspicuous 
flowers  blooming  in  early  spring  and  soon  disappearing. 

c.  S.  cris'pa  Ch.  &  Schl.    Smooth,  with  long,  weak,  trailing  stems. 
Leaves  thin,  ovate,  about  an  inch  long,  with  crisped  margins.     Flowers 
axillary,  on  slender  pedicels.     Sepals  lanceolate,  3-nerved.     Petals 
small,  or  wanting,  white.    Capsule  when  ripe  longer  than  the  sepals. 
Northern  California  to  Alaska,  growing  in  wet,  shady  places  and 
blooming  in  spring  and  summer. 

d.  S.  borea'lis  Bigel.     Generally  smooth  and  erect,  6-10  in.  in 
height.     Leaves  lanceolate,  narrowed  to  a  long  point,  ^-1|  in.  long, 
with  one  prominent  nerve.     Pedicels  often  deflexed,  scattered.     Sepals 
ovate-lanceolate   with   papery   margins,    acute    or   obtuse.      Petals 
shorter  than  sepals  or  wanting.    Pods  narrow,  acute,  nearly  twice  as 
long  as  the  sepals.    Seeds  smooth.    Northern  California  to  Wash- 
ington.    Blooming  in  summer. 


IV.    ARENA'RIA,  Sandwort 

Sepals  separate.  Petals  5,  white,  entire  or  notched.  Sta- 
mens 10.  Styles  3.  Pod  splitting  into  8  valves,  each  with 
2  parts. 


DICOTYLEDONOUS  PLANTS  57 

a.  A.    Douglas'ii   Torr.    &   Gray.      Slender,    low,    much-branched 
annuals.      Leaves    very    narrow,    thread-like.      Flowers    %   in.    in 
diameter,    on   long,    slender   pedicels.     Pod   globose,    equaling  the 
calyx.     Seeds  flat,  smooth.     Throughout  California. 

b.  A.  Califor'nica   Brewer.     Similar   to  the  preceding,  but  with 
lanceolate,  very  short,  obtuse  leaves,  flowers  half  as  large,  capsule 
oblong,  seeds  small  and  rough,  with  minute  points.     Throughout  Cali- 
fornia. 

V.    SPER'GULA,  Corn  Spurry 

Sepals  separate.  Petals  5,  entire.  Stamens  10.  Styles  5, 
alternating  with  the  sepals.  Capsule  5-valved,  with  valves 
opposite  the  sepals. 

S.  arven'sis  L.  Annual,  branching  herbs,  with  fleshy,  thread- 
like leaves  in  whorls.  Flowers  small,  white,  on  long  pedicels  that 
become  reflexed.  Sepals  as  long  as  the  petals  and  a  little  shorter 
than  the  capsule.  This  is  a  common  weed,  blooming  more  or  less 
throughout  the  year. 

VI.    SPERGULA'RIA  (TISSA,  BUDA,  LEPIGONUM),  Sand  Spurry 

Sepals  separate.  Petals  5.  Stamens  10.  Styles  3-5.  Cap- 
sule 3-valved.  Leaves  usually  fleshy,  with  papery  stipules. 
Flowers  white  or  rose-color.  Low  herbs,  usually  growing  near 
the  coast  or  on  alkaline  soil. 

S.  macrothe'ca  Robinson.  Perennial,  much  branched  from  the 
base,  rather  stout.  Flowers  white  or  rose-color,  nearly  £  in.  in 
diameter,  on  pedicels  that  become  nodding.  Capsule  slightly  sur- 
passing the  calyx.  Seeds  smooth  with  a  narrow  wing.  The  large 
ovate  stipules  are  quite  noticeable.  In  salt  marshes  from  Marin 
County  to  San  Diego. 


ILLECEBRA'CEJE 

This  family  is  similar  to  Caryophyllacea},  and  is  included 
winder  the  latter  by  some  botanists.  It  has  an  undivided  or 
2-cleft  style,  a  1-seeded  fruit  (like  an  akene),  and  the  petals 
wanting  or  minute. 


58  KEY   AND   FLORA 


PENTACJE'NA,  Sand  Mat 

Sepals  5,  hooded,  terminating  in  a  spine.  Petals  scale-like. 
Stamens  3-5  at  the  base  of  the  sepals.  Calyx  becoming 
closed  over  the  fruit. 

P.  polycnemoi'des  Bartl.  Perennial  herbs,  forming  mats  of  densely 
flowered  lax  stems.  Leaves  very  small,  tipped  with  sharp  awns  that 
become  recurved.  Stipules  papery,  shorter  than  the  leaves,  but  very 
noticeable.  Flowers  small,  greenish,  sessile,  clustered  in  the  axils. 
This  grows  in  sandy  soil  and  is  common  along  the  seacoast. 


RANUNCULA'CE^,  BUTTERCUP  FAMILY 

Herbs  (Clematis  shrubby)  with  a  colorless,  acrid  juice, 
distasteful  to  animals.  Parts  of  the  flower  ajl  separate  and 
distinct,  inserted  on  the  receptacle.  Petals  often  wanting 
or  peculiar  in  form.  Stamens  numerous ;  fruit  consisting  of 
numerous  akenes  (/.  Fig.  166 ;  e.  Fig.  169),  of  several  follicles 
(/..Fig.  168;  e.  Fig.  171),  or  sometimes  of  berries.  Leaves 
without  stipules,  often  clasping  at  base  (/.  Fig.  97  ;  e.  Fig.  70), 
generally  much  cut  or  divided. 

I.     CLEM'ATIS,  Virgin's  Bower 

Climbing  over  bushes  or  rocks  by  the  leafstalks  of  the  com- 
pound,  opposite  leaves,  or  sometimes  erect  and  not  climbing. 
Sepals  4,  petal-like.  Petals  none  or  very  small.  Pistils  numer- 
ous, forming  a  round  bunch  of  akenes  with  styles  developing 
into  long  feathery  tails. 

a.  C.  ligusticifo'lia    Nutt.      Flowers  dioecious,  in  panicles.     Sepals 
thick,  dull  white,  less  than  ^  in.  long.     Akenes  with  tails  from  1-2 
in.  long.     Widely  distributed. 

b.  C.  lasian'tha  Nutt.      Flowers  dioecious,  solitary,  on  stout  peduncles 
with  one  or  two  bracts.     Sepals  thick,  dull  white,  sometimes  nearly  an 
inch  long.     Fruit  similar  to  above.     In  the  Coast  and  Sierra  Nevada 
Mountains. 

c.  C.   Douglas'ii  Hook.     BUSHY  CLEMATIS.     Stems  erect,  a  foot  or 
two  high,  not  climbing.     Leaves  once,  twice,  or  thrice  pinnately  com- 
pound, with  linear  or  lanceolate  leaflets,  axils  woolly.     Flowers  per- 
fect, usually  solitary  and  terminal,  nodding.     Sepals  leathery,  dark 


DICOTYLEDONOUS  PLANTS  59 

blue,  forming  a  bell-shaped  flower,  more  than  an  inch  long,  with 
spreading  tips.  Tails  to  the  akenes  conspicuous.  This  is  found 
from  Oregon  to  British  Columbia. 

II.    ANEMO'NE,  Windflower,  Anem'ony 

Calyx  of  few  or  many  petal-like  sepals.  Petals  wanting. 
Akenes  pointed  or  with  long  feathery  tails.  Perennial  herbs 
with  stem  leaves  ivhorled,  forming  a  kind  of  involucre  some 
distance  Mow  the  flower. 

III.  THALIC'TRUM,  Meadow-rue 

Flowers  dioecious  in  panicles.  Sepals  ^-7,  greenish.  Petals 
none.  Akenes  in  a  head,  terminated  by  long,  naked  styles. 
Leaves  twice  or  thrice  palmately  compound,  leaflets  3-toothed 
or  lobed,  on  short  petioles.  Generally  tall,  perennial  herbs, 
often  with  a  strong  disagreeable  odor.  The  species  are  diffi- 
cult to  determine. 

IV.  RANUN'CULUS,  Buttercups 

Sepals  5.  Petals  3-15,  each  with  a  little  nectar-secreting 
scale  or  gland  at  the  inside  of  the  base.  Akenes  in  a  head, 
numerous,  usually  flattish.  Stem  leaves  alternate.  Flowers 
generally  yellow.  (There  are  some  that  grow  in  the  water 
with  thread-like  divisions  to  the  leaves  and  small  white 
flowers.) 

a.  R.  Califor'nicus   Benth.     Stems   branching   from  a  cluster  of 
thickened  fibrous  roots,  erect,  hairy.    Root  leaves  of  3  leaflets  with 
3-7   linear   divisions,  or  3-lobed,  with  the  lobes   toothed.      Sepals 
turned  back.    Petals  10-15,  glossy,  yellow,  nearly  £  in.  long.    Akenes 
very  flat,  in  a  round  head  beaked  with  the  stout,  recurved  styles. 
This  is  variable  in  size,  leaves,  and  amount  of  pubescence.    Through- 
out California. 

b.  R.  murica'tus  L.     Stems  stout,  smooth,  hollow.    Flowers  small. 
Akenes    large  with  stout  beaks,  and  the   sides   covered   with    coarse 
prickles.     This  grows  in  wet  places  and  has  been  introduced. 

c.  R.  glaber'rimus  Hook.      Perennial,    with   fleshy   fibrous    roots. 
Stems  3-6  in.  high.     Root-leaves  spatulate  or  wedge-shaped,  entire  or 
with  2-4  blunt  teeth  or  lobes  :  stem  leaves  3-cleft,  ivith  narrow  divisions  or 


60  KEY   AND   FLORA 

entire.  Petals  obovate,  nearly  £  in.  long.  Akenes  in  a  globose  head, 
generally  smooth,  each  tipped  with  a  short  beak.  In  the  Sierra 
Nevada  Mountains  and  northward  to  British  Columbia.  It  blooms 
in  the  spring. 

d.  R.  tenel'lus  Nutt.    Perennial,  a  foot  or  two  high.    Stems  erect, 
hairy,  or  smooth.     Leaves  deeply  lobed,  3-5  cleft,  with  the  divisions 
more  or  less  wedge-shaped,  the   margin  with  a  few  sharp  teeth. 
Petals  5,  small,  yellow.     Akenes  in  a  globose  head,  each  tipped,  with  a 
coiled  style.     Receptacle  smooth.     This  is  widely  distributed  and 
variable.     It  blooms  in  the  spring. 

e.  R.  occidenta'lis   Nutt.     Perennial,  a  foot  or  two  high.     Stems 
widely  branching,    covered  with  widely  spreading   hairs.      Leaves 
deeply  cleft  into  3-5  wedge-shaped  divisions,  these  again  cut  ;  some- 
times the  leaves  are  compound  with  3  leaflets  on  petioles.     Upper 
leaves  simpler  and  smaller.     Petals  5,  twice  as  long  as  the  reflexed 
sepals.     Akenes  tipped  with  flattened,  hooked  beaks  on  a  smooth  recep- 
tacle.    This  is  variable  and  widely  distributed.     It  blooms  in  the 
spring. 

/.  R.  alismaefo'lius  Geyer.  Perennial  from  thick  fibrous  roots. 
Stems  in  bunches,  short  and  erect,  about  6  in.  high.  Leaves  lance- 
shaped,  tapering  to  margined  petioles  that  widen  at  base;  upper  leaves 
thickish,  2-4  in.  long,  nearly  sessile.  Corolla  showy,  yellow,  nearly 
1  in.  across,  with  broad  obovate  petals.  Akenes  in  a  globose  head, 
smooth  with  a  short  beak.  This  grows  in  marshy  places  in  the  Sierra 
Nevada  Mountains  and  northward.  It  blooms  in  the  spring. 


V     AQUILE'GIA,  Columbine  (ALSO  MISTAKENLY  CALLED  Honeysuckle) 

Sepals  5,  petal-like,  all  similar.  Petals  5,  each  consisting  of 
a  tubular  or  expanded  border  terminating  in  a  long  hollow  spur 
projecting  below  the  sepals.  Pistils  5,  forming  many-seeded 
follicles.  Perennial  herbs  with  leaves  twice  or  thrice  pal- 
mately  compound.  Flowers  usually  nodding  at  the  ends  of 
the  branchlets. 

a.  A.  trunca'ta  Fisch  &  Meyer.    RED  COLUMBINE.    Flowers  red, 
tinged   with    yellow.     Sepals    spreading.     Petals    with   scarcely  any 
border,  and  thick,  blunt  spurs.     Throughout  California  growing  in 
shady,  moist  places. 

b.  A.  formo'sa  Fisch.    This  resembles  the  preceding,  except  that 
the  border  of  the  petals  is  prolonged,  especially  on  the  outer  side.    This 
is  found  in  Oregon. 


DICOTYLEDONOUS   PLANTS  61 


VI.    DELPHINIUM,  Larkspur 

Sepals  5,  petal-like,  the  upper  one  prolonged  backwards  at 
the  base  into  a  spur.  Petals  Jf.,  two  running  into  the  calyx  spur, 
the  others  partly  covering  the  pistils  and  stamens.  Flowers  in 
racemes.  Fruit  of  1-5  many-seeded  follicles.  Some  of  the 
species  are  poisonous  to  cattle.  The  blue  Larkspurs  are  the 
most  common,  but  they  are  difficult  to  distinguish. 

a.  D.  nudicaule  Torr.  &  Gray.    Flowers  scarlet,  few,  on  long  pedicels. 
Sepals  close  together,  spur  long.     Stems  almost  leafless,  except  at 
base,  slender  and  delicate.     This  grows  on  moist,  shady  banks  in 
the  Coast  Mountains. 

b.  D.  cardina'le  Hook.     Flowers  bright  scarlet  with  yellow  centers,  in 
a  rather  dense    raceme.     Stems    tall  and  stout.     This  grows  in  the 
mountains  of  southern  California. 

c.  D.  Califor'nicum  Torr.  &  Gray.    Flowers  in  dense  racemes,  bluish 
gray,  woolly  on    the   outside,  spur   horizontal,   equaling   the   sepals. 
Stems  2-8  ft.  high.     Lower  leaves  4-7  in.  in  diameter,  deeply  cleft, 
with   wedge-shaped   divisions.      This  generally  grows  on  dry  hills 
amid  the  brush  along  the  coast. 

VII.    ACONI'TUM,  Aconite,  Monkshood 

Sepals  5,  petal-like,  the  upper  one  like  a  hood  or  helmet. 
The  two  upper  petals  have  long  claws  and  spur-like  blades 
concealed  within  the  hood ;  the  3  lower  are  much  smaller  or 
wanting.  Fruit  of  3-5  many-seeded  follicles. 

A.  Columbia'num  Nutt.  Stems  simple,  leafy,  2-5  ft.  high. 
Flowers  in  a  loose  raceme.  Leaves  palmately  3-5  cleft,  with  wedge- 
shaped,  toothed,  or  cleft  divisions.  This  is  found  at  higher  eleva- 
tions in  the  Sierra  Nevada  Mountains  in  moist,  shady  places.  In 
the  northern  part  of  the  state  it  is  found  at  much  lower  altitudes. 

Vm.    ACT^E'A,  Baneberry 

Perennial  from  short,  branched  rootstocks,  about  a  foot  or 
two  in  height.  Leaves  1  or  2,  with  broad  triangular  outline, 
3-5  times  compound  ;  the  leaflets  ovate,  irregularly  cut  and 
with  the  teeth  on  the  margins  unequal.  Flowers  white,  small, 
in  a  corymb  lengthening  to  a  raceme  and  terminating  the  stem, 
blooming  in  spring.  Fruit  consisting  of  red  or  white  berries 
on 


62  KEY  AND  FLORA 

A.  spica'ta  L.  var.  argu'ta  Torr.  Berries  generally  bright  red, 
oblong  or  roundish,  not  quite  so  large  as  green  peas,  falling  off 
soon  when  ripe.  This  grows  in  shady  woods  and  the  fruit  ripens  in 
late  summer.  It  is  considered  poisonous.  Widely  distributed,  on 
the  coast  and  in  the  mountains. 

IX.    PJEO'NIA,  Pseony 

Stems  several,  from  fleshy  roots,  erect  at  first,  bending  over 
in  fruit.  Leaves  thrice-compound,  leaflets  cut  into  several  seg- 
ments. Flowers  solitary  at  the  ends  of  the  stems.  Sepals  5. 
Petals  5,  concave,  brownish  red.  Stamens  many  on  a  disk. 
Fruit  of  2-5  leathery  follicles  containing  several  large  seeds. 

a.  P.  Califor'nica  Nutt.     Leaves  of  pedate  outline,  scarcely  glaucous. 
Southern  California. 

b.  P.  Brow'nii  Dougl.    Leaves  cordate-ovate  in  outline,  very  glaucous. 
From  the  higher  Sierra  Nevada  Mountains  to  Oregon. 


BERBERIDA'CEJE.     BARBERRY  FAMILY 

Herbs  or  shrubs  with  pinnately  compound  leaves  ;  bracts, 
sepals,  petals,  and  stamens  opposite  each  other  instead  of 
alternating.  Anthers  opening  by  little  valves  hinged  at  the 
top.  Pistil  simple. 

I.    BER'BERIS,  Barberry,  Oregon  Grape 

Mowers  yellow,  in  clustered  racemes  with  bracts.  Sepals  6, 
petal-like.  Petals  and  stamens  6.  Leaves  odd-pinnate,  with 
stiff  spiny-toothed  leaflets.  Fruit,  in  our  species,  a  dark  blue 
berry.  Wood  yellow. 

a.  B.    re'pens   Lindl.     OREGON    GRAPE.     Less   than   a  foot  high, 
from  slender  woody  rootstocks.     Leaflets  3-7,  not  shining,  somewhat 
glaucous,  racemes  few,  terminal.     Northern  California  to  Alaska. 

b.  B.  aquifo'lium  Pursh.     Often  5  or  6  ft.  high ;  leaflets  7-9,  bright 
green  and  glossy,  sinuate-dentate.     Racemes  terminal.     Fruit  nearly 
round.     In  the  Sierra  Nevada  Mountains  from  Kern  County  north- 
ward. 


DICOTYLEDONOUS   PLANTS  63 

c.  B.  pinna'ta  Lag.     From  less  than  a  foot  to  about  2  ft.  high. 
Leaflets  prominently  spiny,  the  lowest  pair  near  the  base  of  the  petiole. 
Racemes   both  axillary  and   terminal.     Hills  of   the  Coast  Moun- 
tains. 

d.  B.  nervo'sa  Pursh.     MAHONIA,  WATER  HOLLY.     Stem  simple, 
bearing  a   crown    of  large    leaves    at   summit,  mixed  with    many    dry, 
chaffy ',  persistent  bracts.    Leaves  1-2  ft.  long,  leaflets  11-17,  somewhat 
palmately  nerved.     Racemes  long.     In  deep  woods  from  Monterey 
northward. 

II.    ACH'LYS,  Oregon  Sweet  Clover  and  Deer's-foot,  Sweet-in-death 

Flowers  on  a  scape  forming  a  spike,  without  sepals  or  petals. 
Stamens  9,  in  3  sets,  with  slender  filaments  and  short  anthers. 
Pistil  with  a  broad,  sessile  stigma  and  a  simple  ovary.  Fruit 
dry  and  indehiscent,  kidney-shaped,  thick  and  rounded  on  the 
back,  thin  and  .concave  on  the  other  side,  with  a  fleshy  ridge 
down  the  center.  Leaves  large,  of  3  leaflets,  having  the  odor 
of  new-mown  hay,  or  vanilla,  when  they  become  dry. 

A.  triphyl'la  DC.  Leaves  and  flowering  stems  from  a  creeping 
rootstock.  Leaves  with  stalks  a  foot  or  more  long  and  with  the 
leaflets  broadly  wedge-shaped,  3-5  in.  long,  palmately  veined  and 
coarsely  and  irregularly  wavy-margined. 

This  is  found  in  northern  California  and  northward  to  British 
Columbia.  It  grows  in  shady  woods  and  is  much  prized  on  account 
of  the  lasting  and  sweet  perfume  of  the  dried  leaves.  It  blooms  in 
spring. 


LAURA'CE^.     LAUREL  FAMILY 

Aromatic  trees  or  shrubs.  Perianth  of  6  petal-like  divi- 
sions. Stamens  9,  in  3  rows,  the  inner  with  3  glands  at  base 
alternating  with  tongue-shaped  staminodia.  Anthers  opening 
as  in  Berber idacece.  Ovary  free,  1-celled,  forming  a  fruit  like 
an  olive. 

UMBELLULA'RIA,  California  Laurel  or  Bay 

Flowers  perfect  in  umbels  which  before  opening  are  in- 
cluded in  involucres  that  are  soon  deciduous. 


64  KEY   AND   FLORA 

U.  Califor'nica  Nutt.  SPICE  WOOD.  A  large,  handsome  tree 
(sometimes  shrubby),  with  smooth  bark.  Leaves  evergreen,  glossy, 
lanceolate-oblong,  on  short  petioles.  Flowers  yellow,  soon  falling. 
Fruit  green  at  first,  dark  purple  or  yellow  when  ripe,  about  1  in. 
long,  solitary,  or  2  or  3  in  a  cluster,  on  a  stout  peduncle.  This  grows 
near  or  not  far  from  water.  Oregon  to  San  Diego.  It  blooms  often 
in  December  or  even  in  November. 


PAP  AVER  A'CE^.     POPPY  FAMILY 

Herbs  or  shrubs.  Parts  of  the  flower  all  separate  (except 
the  sepals  of  Eschscholtzia,  which  are  united),  and  distinct 
on  a  top-shaped  receptacle.  Sepals  falling  off  as  the  petals 
expand  in  the  bud.  Petals  twice  as  many  as  the  sepals, 
generally  4.  Stamens  numerous  and  conspicuous.  Fruit  a 
capsule  with  parietal  placentae.  (In  Platystemon  the  seeds 
are  imbedded  in  the  walls  of  the  capsule  in  rows,  each  row 
forming  a  linear  necklace-like  follicle.) 

I.    ESCHSCHOLT'ZIA,  California  Poppy 

Annual  or  perennial  herbs.  Leaves  bluish  green,  succu- 
lent, usually  cut  into  fine  divisions.  Sepals  united  into  a 
pointed  cap,  often  seen  on  the  opening  flower.  Petals  4)  orange 
or  yellow.  Stamens  numerous,  with  long  anthers.  Stigmas 
2-6.  Pods  long  and  narrow,  ribbed,  usually  dehiscent  from 
the  apex,  the  valves  frequently  remaining  attached  at  the 
sides.  Receptacle  often  surrounded  with  a  rim. 

E.  Califor'nica  Cham.  Annual  or  perennial,  with  succulent  leafy 
sterns.  Flowers  with  a  funnel-form  receptacle  and  a  broad  or 
narrow  rim.  Petals  broad,  yellow  or  orange,  often  the  two  colors 
in  the  same  flower.  This  is  the  commonest  species  and  is  widely 
distributed. 

H.    DENDROME'CON,  Tree  Poppy 

Shrubs  with  erect  branches.  Leaves  alternate,  lanceolate, 
entire,  stiff.  Sepals  2,  large. .  Petals  4)  generally  large,  light 
yellow.  Stigmas  2.  Pod  similar  to  that  of  the  preceding, 
except  that  the  valves  are  generally  dehiscent  from  the  base. 


DICOTYLEDONOUS  PLANTS  65 

D.  rig'ida  Benth.  This  shrub  is  generally  found  on  gravelly  or 
clayey  hills,  growing  to  a  height  of  from  2  to  8  ft.  It  is  conspicuous 
on  account  of  its  numerous  large  yellow  flowers,  which  may  be  found 
at  all  seasons.  The  bark  is  whitish.  It  is  widely  distributed. 


m.    PLATYSTE'MON,  Cream  Cups 

Low,  branching  herbs.  Stem  leaves  opposite  or  whorled, 
entire.  Sepals  3-6,  cream-color,  often  with  a  yellowish  spot 
near  the  base.  Stamens  numerous,  with  flat  filaments. 
Stigmas  linear,  separate,  one  to  each  of  the  necklace-like  pods, 
which  at  first  are  somewhat  united  ;  but  when  ripe  they  sepa- 
rate and  break  apart  between  the  seeds. 

P.  Califor'nicus  Benth.  Stems  branching  from  the  base,  from  6  in. 
to  1  ft.  high.  Leaves  light  green,  hairy,  broad-linear.  Flowers  not 
quite  1  in.  in  diameter.  Pods  from  6-25,  forming  an  oblong  cluster. 
This  is  common  in  early  spring  throughout  California. 


IV.    PLATYSTIG'MA,  Cream  Cups 

Stamens  few  or  many,  with  narrow  filaments.     Pod  with 
3  angles,  splitting  into  3  parts  when  ripe. 

a.  P.  linea're  Benth.     This   resembles    Platystemon,   but   can   be 
distinguished  by  the  3  stigmas  and  the  3-angled  pods. 

b.  P.  Califor'nicum  Benth.  &  Hook.    Steins  long  and  slender,  with 
branches  2-forked,  smooth.     Flowers  small,  white.     Stamens   about 
12  in  2  circles.     Pod  about  1  in.  long,  narrowly  linear.     This  is  less 
common,  and  generally  grows  in  the  shade.     Santa  Barbara  County 
to  Oregon. 


V.    ARGEMO'NE,  Prickly  Poppy,  Mexican  Poppy,  Thistle  Poppy, 
Chicalote 

Herbs  with  stout  pale-green  stems,  and  foliage  more  or  less 
covered  with  spines  or  prickles.  Sap  yellow.  Leaves  thistle- 
like.  Flowers  large,  white.  Sepals  3,  each  with  a  spine- 
like  beak,  forming  a  3-horned  bud.  Petals  4-6.  Stamens 
numerous,  on  slender  filaments.  Pods  1-celled,  opening  at 
the  top  into  3-6  parts,  the  ribs  remaining  fastened  to  the 
united  stigmas. 


66  KEY   AND   FLOE  A 

A.  platy'ceras  Link.  &  Otto.  Stems  smooth  under  the  dense  white 
prickles.  Flowers  3-4  in.  broad.  Ovary  densely  covered  with  erect 
prickles.  Central  and  southern  California. 

VI.    ROMNE'YA,  Matilija  (MATII/IHA)  Poppy 

Smooth,  stout,  perennial  herbs,  several  feet  high,  with 
colorless  sap.  Leaves  alternate,  pinnately  cut  or  divided, 
not  spiny.  Sepals  3,  each  with  a  broad  winy  on  the  back. 
Petals  6)  large,  white.  Stamens  many,  with  filaments  dimin- 
ishing towards  the  base.  Ovary  covered  with  bristles.  Pod 
7-1 1-celled,  the  sides  separating  from  the  placenta. 

a.  R.  Courteri  Harv.    This  beautiful  plant  is  native  in  the  south- 
ern part  of  the  state.     It  is  now  widely  cultivated.     The  flowers  are 
sometimes  6  in.  in  diameter.      The  buds  are  smooth.     This  grows  in 
southern  California  and  is  extensively  cultivated. 

b.  R.  trichoca'lyx  Eastwood.     This  is  similar  to  the  above,  but  the 
buds  are  hairy  and  the  stems  are  not  so  robust.     The  dissected  leaves 
are  close  under  the  flowers.     This  is  the  true  Matilija  poppy,  since 
it  is  the  species  found  in  the  canon  of  that  name. 

VII.    MECONOP'SIS,  Poppy 

Annual  herbs  with  yellow  sap.  Leaves  variously  cut  into 
linear  divisions.  Sepals  2.  Petals  red  or  orange.  Stamens 
numerous.  Stigma  4-8-lobed,  on  a  distinct,  stout  style.  Pod 
1-celled,  with  the  valves  separating  as  in  Romneya. 

M.  heterophyl'la  Benth.  FLAMING  POPPY.  Smooth-  and  slender 
herbs  with  succulent  sterns  and  pale-green  leaves.  Flowers  on  long 
slender  peduncles,  exceedingly  variable,  from  less  than  1  in.  to  2  in. 
in  diameter,  with  pale-red  petals  becoming  darker  and  more  glow- 
ing at  the  center.  Throughout  California. 


FUMARIA'CE.35.     BLEEDING  HEART  FAMILY 

Perennial  herbs.  Leaves  compound,  cut  into  many  narrow 
divisions.  Flowers  of  peculiar  shape.  Sepals  2,  petals  4, 
stamens  6  in  2  sets,  with  the  filaments  of  each  set  somewhat 
united,  the  middle  anthers  2-celled,  the  others  1-celled.  Pod 
1-celled,  with  the  valves  separating  from  the  placenta. 


DICOTYLEDONOUS   PLANTS  67 


I.    DICEN'TRA,  Bleeding  Heart 

Sepals  2,  like  scales.  Corolla  heart-shaped,  the  2  outer 
petals  swollen  at  the  base,  and  with  spreading  tips ;  the  2 
inner  narrow,  spoon-shaped,  with  a  crest  or  keel  on  the  back, 
united  at  the  tips  and  covering  the  anthers  and  stigma. 
Style  slender.  Stigma  2-lobed,  each  lobe  2-crested,  and  so 
appearing  4-lobed. 

a.  D.  formo'sa  DC.     BLEEDING    HEART.     Leaves   and   flowering 
stems  springing  from  creeping  rootstocks,  succulent  and  pale  green, 
1   or  2   ft.   high.      Flowers  rose-color,   in  compound   racemes.      This 
grows  in  rich  soil  in  the  shade.    From  the  Sierra  Nevada  Mountains 
to  British  Columbia. 

b.  D.  chrysan'tha   Hook.  &  Arn.      GOLDEN  EARDROPS.    Flowers 
golden   yellow,  in    compound    racemes.       Stems    leafy,  stout,  2-4  ft. 
high.     Leaves  twice  pinnately  compounded,  often  more  than  1  ft. 
long.      Sepals    soon    falling.       Flowers    more    than    ^  ~$n.    long. 
This   showy    plant   grows   in  sunny   places,    usually   on  dry  hills, 
throughout  California.     It  is  not  common. 


CRUCIF'ER^.    MUSTARD  FAMILY 

Herbs  with  pungent,  watery  juice.  Leaves  alternate  with- 
out stipules.  Flowers  in  racemes,  spikes,  or  corymbs.  Sepals 
usually  4,  often  falling  early.  Petals  4,  with  the  blades  in 
the  form  of  a  cross.  Stamens  6,  the  2  outer  ones  shorter  than 
the  2  inner.  Fruit  a  pod  divided  into  2  parts  (except  in  the 
first  2  genera)  by  a  transparent  partition  which  stretches 
from  one  placenta  to  the  other.  The  flowers  of  this  family 
are  so  alike  that  genera  and  species  cannot  be  determined 
without  examining  tolerably  mature  fruit. 

*Pod  not  elongated,  flowers  usually  very  small. 
I.    THYSANOCAR'PUS,  Lace  Pod 

Flowers  inconspicuous,  white,  fruit  roundish,  indehiscent, 
1 -seeded,  surrounded  by  a  prominent  wing,  which  is  crenate, 
filled  with  small,  regular  holes  like  embroidery,  or  with  lines 


68  KEY   AND   FLORA 

radiating  from  the  seed  to  the  margin.  Erect,  branching, 
annual  herbs,  with  leaves  sessile  and  generally  auriculate- 
clasping. 

a.  T.  cur'vipes  Hook.     This  is  the  commonest  species.     It  has  the 
fruit  with  crenate  margin,  often  perforated.     Widely  distributed. 

b.  T.  ra'dians  Benth.    This  has  much  larger  fruit  than  the  preced- 
ing, with  lines  radiating  from  the  center  to  the  outside  of  the  wing. 
This  is  found  from  California  to  Oregon. 


H.    ATHY'SANUS 

Flowers  very  small.  Fruit  roundish,  not  winged,  generally 
covered  with  hooked  prickles,  indehiscent  and  1-seeded.  Low, 
spreading,  slender,  delicate,  hairy  herbs,  fruiting  in  spring. 

A.  pusillus  Greene.  This  is  the  only  species.  It  is  widely 
distributed. 

HI.    LEPID'IUM,  Peppergrass 

Flowers  small,  white  or  greenish,  with  petals  often  want- 
ing. Fruit  roundish,  usually  notched  at  the  apex,  2-celled, 
flattened  contrary  to  the  partition. 

a.  L.  nit'idum  Nutt.     Low  annuals.     Pods  shining,  reddish,  very 
numerous.     Leaves  compound,  with  narrow,  linear  leaflets.     This  is 
one  of  the  earliest  plants  of  spring.     Widely  distributed. 

b.  L.  bipinnatif'idum   Desv.     Low,  almost   prostrate   herbs,  with 
the   lowest  leaves   twice    divided,  and    divisions   usually  roundish. 
Petals  wanting.    Pods  round,  on  stout  spreading  pedicels.    Introduced, 
Common  on  roads  and  streets. 

c.  L.  apet'alum  Willd.     Stems  slender,  a  foot  or  so  high,  branch- 
ing.    Lower  leaves  toothed  or  more  deeply  divided,  acute  at  apex. 
Flowers  without  petals,  on  erect  pedicels  that  spread  widely  in  fruit. 
Pods  smooth,  round,  notched  at  apex.     This  is  a  weed  which  has  been 
introduced  and  is  now  widely  distributed. 


IV.    SENEBIE'RA,  Wart  Cress 

Flowers  greenish.  Pod  of  2  globose,  equal  parts  united,  form- 
ing a  twin  pod.  Leaves  pinnately  parted.  Low,  spreading, 
introduced  plants  with  a  disagreeable  odor. 


DICOTYLEDONOUS   PLANTS  69 

S.  pinnatif'ida  DC.  This  is  found  along  the  coast,  growing  near 
flumes,  drains,  roads,  etc. 

V.    CAPSEI/LA,  Shepherd's  Purse 

Flowers  small,  white.  Pods  elliptical  or  obcordate,  2-celled, 
flattened  contrary  to  the  partition.  Erect  branching  herbs 
with  the  leaves  clustered  at  the  base. 

C.  Bursa-pasto'ris  Medic.  SHEPHERD'S  PURSE.  This  is  the  com- 
mon dooryard  weed,  with  obcordate  pods  in  loose  raceme. 


**  Pod  elongated.    Flowers  generally  conspicuous. 
VI.    RAPE' ANUS,  Radish 

Pod  beaked,  compressed  between  the  seeds.  Flowers  large, 
orange,  white  or  rose-purple,  veined.  These  are  coarse,  hairy, 
erect,  branching  herbs  with  fleshy  roots.  Leaves  cut  into 
several  divisions,  the  upper  one  much  the  largest. 

R.  sati'vus  L.  This  is  the  common  radish  which  grows  wild 
throughout  the  settled  parts  of  California.  The  petals  are  purplish, 
and  the  fruit  is  not  strongly  compressed  between  the  seeds. 

VH.    BRAS'SICA,  Mustard 

Pod  slender,  terete,  2-celled,  ivith  a  flattened  beak.  Flowers 
yellow.  All  probably  introduced  weeds. 

a.  B.  campes'tris   L.      WHITE    MUSTARD.      Flowers   in    a   loose 
raceme.     Leaves  bluish  green,  smooth,  clasping.     Pods  large,  spread- 
ing.    This  is  very  common  and  is  in  bloom  earlier  than  the  other 
species. 

b.  B.  ni'gra  Koch.    BLACK  MUSTARD.     Flowers  in  close  racemes 
at  the  ends  of  long  stems,  fragrant.     Petals  twice  as  long  as  the 
sepals.     Pods  rather  small,  erect  as  if  clinging  to  the  stem.     Stems  often 
very  tall.     This  is  common  throughout  California. 

Vm.    ERYS'IMUM,  Wallflower 

Pods  spreading  or  erect,  1-5  in.  long,  2-4-sided,  with  thick 
walls.  Flowers  fragrant,  yellow  or  orange,  at  first  in  a 


70  KEY   AND   FLORA 

corymb,  which  lengthens  to  a  raceme.  Petals  with  blade 
^  in.  long.  Erect  rough  herbs,  with  leaves  linear  or  lanceo- 
late. 

a.  E.  as'perum,  DC.     Stems  generally  simple,  often  tall.    Flowers 
generally  orange.     Pods  4-sided.     Widely  distributed  and  variable, 
especially  in  the  color  of  the  flowers. 

b.  E.    grandiflo'rum   Nutt.       Stems    1    or   2    ft.    high,    simple    or 
branched  from  the  base.     Flowers  in  a  corymb,  yellow,  becoming- 
paler  after  pollination.    Pod  2-sided,  flattened  contrary  to  the  partition. 
From  Oregon  to  Los  Angeles,  not  far  from  the  coast.    This  includes 
many  forms. 

IX.    NASTURTIUM,  Cress 

Pods  short,  oblong  or  linear,  with  thin  walls.  Flowers  small, 
yellow  or  white.  Leaves  usually  pinnately  divided. 

N.  officina'le  L.  WATER  CRESS.  This  is  common  in  all  the 
streams. 

X.    BARBARE'A,  Wintercress,  Yellow  Rocket 

Pods  somewhat  J^-sided,  flattened  parallel  to  the  partition, 
about  1  in.  long,  spreading  upwards.  Seeds  in  1  row  in 
each  cell.  Flowers  yellow,  with  petals  twice  as  long  as  the 
sepals,  in  a  short,  dense  raceme.  Loiver  leaves  compound,  with 
the  terminal  leaflet  rounded  and  larger  than  the  others  ;  upper 
leaves  generally  simple. 

B.  vulga'ris  R.  Br.  This  is  the  only  species.  It  grows  in  damp 
places  and  blooms  in  early  spring.  Widely  distributed. 


XI.    PLATYSPER'MUM 

Flowers  very  small,  solitary,  on  naked  scapes.  Sepals  broad, 
erect,  equaling  the  white,  linear-spatulate  petals.  Pods  almost 
orbicular,  with  broadly  winged,  veiny  seeds  in  2  rows.  Leaves 
lyrate,  with  few  lobes  or  almost  none. 

P.  scapig'erum  Hook.  Scapes  1-6  in.  in  height  in  fruit.  Flowers 
about  T1^  in.  long.  Pod  £-£  in.  long,  containing  8-12  seeds.  This 
is  found  on  the  eastern  slope  of  the  Sierra  Nevada  Mountains  from 
California  north  to  Washington.  It  blooms  in  early  spring. 


DICOTYLEDONOUS   PLANTS  71 


XII.    DENTA'RIA,  Toothwort,  Pepper-root 

Pods  linear,  flattened  parallel  with  the  partition,  walls 
firm  without  nerves,  stigma  short.  Seeds  in  1  row,  wingless. 
Flowers  large,  pale  rose-color  or  milky  white. 

D.  Califor'nica  Nutt.  MILKMAIDS.  Rootstocks  bearing  tubers 
which  easily  break  off.  Root  leaves  simple  and  round-kidney-shaped 
or  with  3  leaflets  (usually  not  found  on  the  blooming  plant)  ;  stem 
leaves  with  from  3  to  5  pinnate  leaflets  on  petioles.  This  is  one  of 
the  loveliest  and  most  common  of  the  early  spring  flowers,  usually 
found  in  damp  places.  Widely  distributed  in  the  Coast  Mountains. 

XIII.    CARDA'MINE 

Pods  linear,  flat,  with  the  seeds  in  1  row,  wingless.  This 
is  similar  to  Dentaria,  but  has  smaller  floiuers,  narrower  pods, 
and  smaller  seeds.  The  chief  differences  lie  in  the  cotyledons, 
which  in  Cardamine  are  flattened,  while  in  Dentaria  they  are 
thick,  unequal,  and  oblique. 

C.  oligosper'ma  Nutt.  Annual,  slender,  hairy  or  smooth.  Leaves 
pinnately  divided,  with  small  3-5  lobed  or  toothed  divisions  which 
are  on  small  petioles.  Flowers  small,  \  in.  long,  white,  in  few- 
no  wered  racemes,  on  short  peduncles.  Pods  erect,  on  short  stipes 
and  containing  8-20  seeds.  This  grows  in  shady,  damp  places  ;  it 
blooms  in  the  spring  and  is  widely  distributed  along  the  Pacific 
Coast. 

XIV.    AR'ABIS,  Rock-cress 

This  is  similar  to  the  preceding,  except  that  the  walls  of  the 
jxx/x  are  nerved,  roots  woody,  and  seeds  usually  with  a  border 
or  wing.  Flowers  white  or  rose-color,  often  conspicuous. 

«.  A.  perfolia'ta  Lam.  TOWER  MUSTARD.  Biennial  herbs  with 
stems  bluish  green,  erect,  1  or  2  ft.  high.  Stem  leaves  arrow-shaped 
and  clasping.  Root  leaves  hairy,  soon  withering.  Flowers  small, 
white.  Pods  numerous,  slender,  erect,  parallel,  and  close  to  the  stem. 
Seeds  generally  narrowly  winged.  Widely  distributed. 

b.  A.  blepharophyl'la  Hook.  &  Arn.  Stems  low,  from  a  tuft  of 
broadly  spatulate,  dark-green  leaves,  with  long  hairs  on  the  margins. 
Flowers  large,  fragrant,  reddish  purple.  Pods  beaked,  flat,  loosely 
spreading.  Seeds  with  a  narrow  wing,  in  1  row.  This  is  perennial  and 
is  found  on  rocky  hills  near  the  coast  from  San  Francisco  to  Monterey. 


72  KEY   AND   FLORA 

c.  A.   hirsu'ta  Scop.     Biennial,   hirsute   especially   at  base,  with 
spreading  hairs  which  are  simple  or  forked.     Steins  erect,  simple 
or  branched,   1-3  ft.  high.     Leaves  at  base  oblanceolate,  coarsely 
toothed  or  entire,  1-2  in.  long,  on  winged  petioles;  stem  leaves  cor- 
date or  auricled  at  base.     Flowers  very  small.    Petals  greenish  white. 
Pods  erect  on  slender  pedicels,  very  narrow,  1-2  in.  long;  stigmas 
nearly  sessile.      Seeds   with   a  narrow    margin.      This   blooms    in 
spring  and  is  found  from  northern  California  to  Alaska. 

d.  A.    Holboeriii  Hornem.     Biennial,    clothed   with   fine   stellate 
pubescence.     Stems  1-several,  simple  or  branched.     Leaves  at  base 
oblanceolate,  narrow,  entire.     Stem  leaves  arrow-shaped.     Flowers 
becoming  deflexed  and  generally  growing  on  one  side  of  the  pedun- 
cle.    Petals  white  or  pink,  £  in.  long.     Pods  fiat,  refiexed ;  stigmas 
sessile.     Seeds  in  1  row,  orbicular,  winged.     This  blooms  in  the  spring 
and  is  very  widely  distributed. 

XV.    STREPTAN'THUS,  Jewel-flowers 

Pods  linear-oblong,  flattened  parallel  with  the  partition, 
on  a  broad  receptacle.  Seeds  flat,  with  a  margin  or  wing. 
Sepals  usually  bright  purple  or  white,  uniting  somewhat  to 
form  a  closed  calyx.  Petals  narrow,  with  spreading  blades. 
Anthers  long,  arrow-shaped;  filaments  of  the  larger  stamens 
often  united  into  2  pairs.  The  species  are  numerous  and 
difficult  to  distinguish. 


XVI.    STANFOR'DIA  (NAMED  FOR  HON.  LELAND  STANFORD). 

Pods  linear  oblong,  flattened  contrary  to  the  partition. 
Stigma  2-lobed,  on  well-developed  pods.  Otherwise  similar 
to  Streptanthus. 

S.  Califor'nica  Watson.  This  is  the  only  species.  It  is  found  in 
the  southern  San  Joaquin  Valley,  where  it  is  very  abundant  in  some 
parts  in  early  spring. 


XVII.    CAULAN'THUS,  Wild  Cabbage 

Pods  terete,  or  .somewhat  flattened,  parallel  with  the  par- 
tition. Flowers  similar  to  the  two  preceding,  except  that  the 
petals  have  broad  claws,  and  the  blades  are  scarcely  evident. 
Tall  herbs,  often  with  inflated  stems.  The  species  are  mostly 
local  and  not  readily  distinguished. 


DICOTYLEDONOUS   PLANTS  73 


XVIII.    THELYPO'DIUM 

Pods  slender,  terete,  or  4-sided,  and  often  twisted,  on  a 
slender  stipe.  Flowers  white  or  purplish.  Stamens  long, 
conspicuous,  with  very  narrow,  arrow-shaped  anthers.  Sepals 
at  first  united  to  form  a  tube,  afterwards  spreading. 

T.  lasiophylluni  Greene.  Erect,  smooth  below,  hairy  above. 
Leaves  toothed  or  pinnately  lobed  or  divided,  with  spreading  seg- 
ments. Flowers  small,  yellowish  white.  Pods  slender,  narrowed  to 
the  apex,  deflexed  on  curved  pedicels.  (One  variety  has  erect  pods.) 
This  is  common,  especially  in  cultivated  ground. 

XIX.    STANLE'YA 

Pods  long  and  terete  on  a  raised  receptacle,  with  1  row  of 
seeds  in  each  cell.  Flowers  bright  yellow  or  cream-color,  with 
long,  narrow,  spatulate  petals  with  slender  claws ;  anthers 
linear,  spirally  coiled,  on  long  filaments. 

S.  pinnatif'ida  Nutt.  GOLDEN  PRINCE'S  PLUME.  This  is  the 
only  known  California!!  species.  The  long  conspicuous  stamens 
and  the  long,  loosely  and  thickly  flowered  plume-like  clusters  of 
golden-yellow  flowers  suggested  the  common  name  to  Helen  Hunt 
Jackson.  Southern  California,  common  in  arid  districts. 


CAPPARIDA'CEJE.     CAPER  FAMILY 

Herbs  or  shrubs  with  alternate  palmately  compound  leaves 
of  3  leaflets.  Flowers  as  in  Cmicifercu,  except  that  the 
stamens  are  all  equal.  Pods  on  long  stipes,  1-celled,  with 
2  parietal  placentae.  Many  flowers  have  the  pistil  rudimen- 
tary and  never  produce  fruit. 

ISO'MERIS,  Bladderpod 

Shrubby,  with  hard,  yellow  wood.  Leaflets  as  long  as  the 
petiole.  Flowers  in  racemes  with  bracts,  generally  simple. 
Corolla  yellow,  %  in.  in  diameter.  Pods  inflated,  pear-shaped, 
drooping,  on  long  slender  stipes. 

I.  arbo'rea  Nutt.  This  is  the  only  species.  It  is  found  in  south- 
ern California,  where  it  is  quite  common. 


74  KEY   AND   FLORA 


CRASSULA'CE^S).     STONECROP  FAMILY 

Thick,  fleshy  herbs.  Sepals,  petals,  stamens,  and  pistils 
all  of  the  same  number,  or  stamens  twice  that  number.  The 
pistils  become  follicles  in  fruit. 

I.    SE'DUM,  Stonecrop 

Sepals  4  or  &•>  united  at  base.  Petals  distinct,  spreading, 
star-like.  Flowers  in  cymes,  generally  on  one  side  of  the 
flowering  axis,  deep  purple,  yellow,  or  white.  No  one  species 
is  widely  distributed  in  California. 

a.  S.  spathulifo'lium  Hook.     Perennial.     Stems  spreading  by  run- 
ners and  rooting  at  the  rose-like  bunches  of  fleshy  leaves.     Leaves 
glaucous,  obovate  or  spatulate,  flat,  £-3  in.  long.     Flowering  stems 
erect,  capped  by  a  cyme  of  yellow  flowers,  which  are  almost  sessile,  and 
disposed  to  be  on  one  side  of  the  peduncles.     Petals  twice  as  long  as 
the  ovate  sepals,  a  little  longer  than  the  stamens  and  style.     This 
blooms  in  summer.     It  grows  on  rocks  that  are  clothed  with  moss 
and  are  wet  during  the  rainy  season,  but  later  become  dry.      It  is 
common  from  middle  California  to  Washington. 

b.  S.  Orega'num  Nutt.     This  is  similar  to  the  above  but  is  not 
glaucous.    Flowers  larger.    Petals  pale  rose-color,  narrowly  lanceolate, 
with  pointed  apex,  nearly  twice  as  long  as  the  stamens.     This  is 
found  from  northern  California  to  Washington. 

c.  S.  pu'milum  Benth.     Annual,  slender,  with   stems   simple   or 
branched,  1—6  in.  high.     Leaves  ^  in.  long,  ovate-oblong.     Flowers 
yellow,    sessile,    in    cymes.       Calyx    lobes    very    small,    triangular, 
acute.      Petals   linear,   acute,    exceeding   the    calyx,    stamens,    and 
styles.     Follicles  1-seeded,   with   the  seed  filling  the  cavity.     This  is 
widely   distributed   in    the    Coast    and   Sierra   Nevada   Mountains. 
It  blooms  in  summer  and  generally  grows  on  northward  slopes  or 
on  shady  rocks. 

II.     COTYLE'DON  (ECHEVERIA) 

Calyx  5-parted.  Petals  united  into  a  cylindrical  corolla. 
Stamens  10,  on  the  tube  of  the  corolla.  Leaves  entire,  thick, 
and  fleshy,  forming  large  clusters  at  the  base  of  the  flowering 
stem.  Flowers  red  or  yellow,  in  long  racemes  or  cymes, 
coiled  somewhat  at  the  tip.  The  species  are  difficult  to 
distinguish  and  mostly  local. 


DICOTYLEDONOUS   PLANTS  75 


SAXIFRAGA'CE^.     SAXIFRAGE  FAMILY 

Herbs  or  shrubs.  Leaves  opposite*  or  alternate  without 
stipules.  Calyx  either  free  from  or  partially  united  to  the 
ovary.  Petals  and  stamens  inserted  on  the  calyx.  Stamens 
not  more  than  twice  the  number  of  calyx  lobes.  Carpels 
2-5,  partially  or  completely  united  into  a  compound  ovary. 
Styles  distinct.  Seeds  with  endosperm.  In  the  currants  and 
gooseberries  the  fruit  forms  a  berry. 

I.    SAXIF'RAGA,  Saxifrage 

f 

Herbs  with  simple  or  palmately  lobed  leaves  and  cymose 
or  panicled  flowers.  (Flowers  rarely  solitary.)  Calyx  5-lobed, 
either  free  from  the  ovary  or  with  the  lower  part  of  the 
tube  coherent.  Petals  5,  entire,  inserted  on  the  calyx  tube. 
Stamens  10.  Capsule  consisting  of  2  carpels  united  at  the 
base,  the  styles  soon  diverging  and  becoming  beaks  on  the 
akenes.  Placenta  axillary.  Leaves  often  in  radical  clusters 
and  flowers  on  a  scape. 

S.  Calif or'nica  Greene.  Leaves  few,  rather  thick,  somewhat 
clothed  with  glandular  hairs,  oval  to  elliptical,  on  broad  petioles ; 
margin  crenate  or  dentate.  Scape  6-18  in.  high;  flowers  in  a  loose 
panicle.  Calyx  nearly  free  from  the  ovary,  with  reflexed  sepals. 
Petals  oblong,  white,  thrice  as  long  as  the  sepals.  Stamens  with 
filaments  inserted  under  the  edge  of  a  disk  which  equals  the  summit 
of  the  ovary.  Blooming  in  early  spring  and  found  on  cool  slopes 
throughout  California. 

II.    BOYKIN'IA 

Perennial  herbs  with  creeping  rootstocks,  leafy  stems,  and 
paniculate  corymbs  or  cymes  of  small  white  flowers.  Leaves 
alternate,  round-kidney-shaped,  palmately  lobed  or  toothed, 
the  teeth  glandular  at  tip ;  petioles  with  stipule-like  dilations 
at  base.  Calyx  5-lobed,  with  globular  tube,  adherent  to  the 
ovary.  Petals  5,  entire.  Stamens  5,  with  short  filaments. 
Pod  splitting  down  the  beaks,  2-celled. 

B.  occidentals  T.  &  G.  Diffusely  branched,  with  slender  stems 
1  or  2  ft.  high.  Leaves  somewhat  scattered,  thin,  5-7-lobed,  1-3  in. 


76  KEY   AND   FLORA 

broad;  petioles  with  brown  bristles  at  base.  Calyx  with  urn- 
shaped  tube  and  triangular  lobes.  Petals  recurved  in  age,  wedge- 
shaped.  This  grows  along  rocky  streams  from  middle  California  to 
British  Columbia.  It  blooms  in  the  summer. 


III.    TELLFMA 

Perennial  herbs  from  rootstocks  or  tubers.  Leaves  mostly 
radical,  round-cordate,  toothed  or  palmately  divided,  with 
petioles  dilated  at  base.  Flowers  in  a  simple  raceme.  Calyx 
bell-shaped  or  urn-shaped,  with  the  base  attached  to  the  loiver 
half  of  the  ovary.  Petals  5,  fringed,  lobed,  or  entire,  white 
or  rose-color.  Stamens  10.  Styles  2  or  3,  short,  with  round 
stigmas.  Capsule  slightly  beaked  by  the  persistent  styles,  and 
opening  between  the  beaks. 

a.  T.  grandiflo'ra  Dougl.     FRINGED   CUPS.     Stems  rather  stout, 
1-2  ft.  high,  from  a  woody  rootstock.    Radical  leaves  2-4  in.  broad. 
Flowers  with  inflated  calyx  and  petals  rose-color,  fringed.     This  grows 
in  moist,  shady  places.     From  Santa  Cruz  to  Alaska. 

b.  T.  af'finis  Bolander.     Stems  slender,  about  a  foot  high,  from 
a   tuber-bearing    rootstock.      Radical   leaves   rouiid-kidney-shaped, 
slightly  lobed;   stem  leaves  3-lobed  to  the  middle,  with  coarsely 
toothed  lobes.     Calyx  narrowed  at  base,  with  its  tube  adhering  to  the 
ovary.      Petals   white,    the    lower    3-toothed,    the    upper   narrower, 
shorter,  and  entire.     In  shady  places  almost  throughout  the  state. 

c.  T.  heterophyl'la  Hook.  &  Am.     Similar   to  the  preceding  in 
stem   and   general   appearance.      Radical    leaves   with   5   shallow, 
rounded  lobes,  stem  leaves  more  deeply  3-lobed  or  parted.     Calyx 
bell-shaped,  the  base  adhering  to  the  ovary.     Petals  3-lobed.     Common 
in  the  Coast  Mountains,  in  shady  places. 

d.  T.  parviflo'ra   Hook.     Stems  slender,  about  a  foot  in  height, 
clothed  with  rough  pubescence.     Leaves  3-5-parted,  with  the  divi- 
sions wedge-shaped  and  cleftJnto  narrow  lobes.    Calyx  wedge-shaped, 
half  adhering  to  the  ovary.     Petals  3-cleft,  with  the  divisions  linear  or 
oblong.     Besides  the  bulblets  on  the  slender  rootstocks,  there  are 
generally  some  on  the  few-flowered  raceme.     Blooming  in  spring 
and  found  from  northern  California  to  British  Columbia. 

e.  T.  tenella  Watson.     Stems  slender,  2-9  in.  high,  rough  with 
glandular  pubescence.     Leaves  similar  to  the  preceding  but  smaller. 
Calyx  bell-shaped,  with  the  base  roundish  or  acute,  adherent  only  at  base. 
Petals  3-7-parted  into  linear  divisions.     This  also  has  bulblets  on 
the  rootstock  and  racemes.     Blooming  in  spring  and  found    from 
northern  California  to  Washington. 


DICOTYLEDONOUS  PLANTS  77 


IV.    TOLMIE'A 

Perennial  herbs  with  slender,  creeping  rootstocks  and  some- 
times runners.  Leaves  mostly  from  the  root.  Flowers 
small,  in  a  loose  raceme.  Calyx  funnel-form,  free  from  the 
ovary,  thin  and  swollen  at  base,  with  unequal  lobes.  Petals  4-5, 
thread-like,  recurved,  persistent.  Stamens  3,  inserted  in  the 
throat  of  the  calyx  ;  filaments  short,  and  anthers  with  the 
2  cells  running  into  one.  Pod  oblong,  with  the  base  tapering 
to  a  short  stem,  splitting  between  the  diverging  equal  beaks. 

T.  Menzie'sii  T.  &  G.  Stems  1-2  ft.  high,  hairy  with  stiff  hairs. 
Leaves  round,  heart-shaped,  crenately  toothed  ;  petioles  slender ;  stem 
leaves  few.  Raceme  nearly  a  foot  long,  flowers  greenish  or  purplish, 
nearly  £  in.  long,  including  the  capsule.  Blooming  in  spring  and 
summer  and  found  from  northern  California  to  Washington. 


•  V.    HEtTCHERA,   Alum  Root 

Perennial  herbs  from  stout  rootstocks.  Leaves  all  radical, 
cordate,  lobed  and  toothed,  the  veins  often  colored  red. 
Flowers  small  in  a  panicle.  Calyx  generally  campanulate, 
with  base  attached  to  the  lower  half  of  the  ovary.  Petals  5, 
entire,  small,  soon  falling.  Ovary  and  capsule  1-celled,  with 
2  parietal  placentce  and  2  styles  which  become  beaks  on  the 
capsule. 

a.  H.  inicran'tha  Dougl.     This  is  the  commonest  species.     It  is  con- 
spicuous on  moist,  shady  banks  because  of  its  beautiful  red- veined 
leaves.      The  flowers  are  quite  small,  and.   the  panicle   is  loosely  and 
numerously  flowered.     Common  in   shady  places   in  the  Coast  and 
the  Sierra  Nevada  Mountains. 

b.  H.  cylin'drica  Dougl.     Leaves  all  from  the  root,  round-kidney- 
shaped,  lobed  or  crenately  toothed,  1-2  in.  broad.     Flowers  greenish, 
in  spikes,  terminating  leafless  scapes,  1-2  ft.  high.     Calyx  lobes  erect, 
oblong,  and  elongated.     Petals  very  small  or  wanting.     Stamens  and 
style  short.     Blooming  in  spring.     Washington  and  Oregon. 


VI.    TIAREL'LA 

Perennial  herbs  with  simple  or  compound  leaves  with 
stipules.  Flowers  small,  white,  in  a  panicle  or  raceme. 
Calyx  5-parted,  with  valvate  lobes.  Petals  5,  entire,  with 


78  KEY   AND   FLORA 

claws.  Stamens  10,  inserted  with  the  petals  at  the  base  of 
the  calyx.  Anthers  2-celled.  Ovary  1-celled,  of  2  valves,  which 
soon  separate  and  become  unequal,  one  elongating,  the  other 
remaining  short.  Seeds  few  at  the  base  of  the  placentae. 
Blooming  in  summer  and  found  from  northern  California  to 
British  Columbia. 

T.  unifolia'ta  Hook.  Stems  slender,  £-!£  ft.  high.  Leaves 
ovate-cordate,  3-5-lobed;  those  from  the  root  on  long  petioles; 
stem  leaves  few,  on  short  petioles.  Panicle  narrow.  This  is  found 
in  shady  woods  from  northern  California  to  British  Columbia.  It 
blooms  in  the  summer. 


VII.    RI'BES,  Currant,  Gooseberry 

Shrubs  with  alternate,  palmately  veined  and  lobed  leaves. 
Flowers  solitary  or  in  racemes  at  the  ends  of  leafy  branchlets, 
sometimes  blooming  before  the  leaves.  Calyx  with  tube 
attached  to  the  globose  ovary  and  extending  beyond  it,  the 
border  4  or  5  cleft,  usually  colored.  Petals  erect,  smaller 
than  the  calyx  lobes.  Stamens  alternating  with  the  petals. 
Fruit  a  berry,  smooth  or  prickly,  containing  many  seeds,  and 
generally  surmounted  by  the  withered  remains  of  the  flower. 

a.  R.  specio'sum  Pursh.    FUCHSIA-FLOWERED  GOOSEBERRY.    Tall, 
with  prickly  branches  armed  with  3  large  thorns  under  each  cluster 
of  leaves.     Leaves  thick,  small,  smooth,  nearly  evergreen.     Flowers 
2—5,  on  a  glandular-bristly  peduncle,  bright  red,  with  the  parts  four, 
almost   1    in.    long,   drooping.      Stamens  protruding  from    the    corolla. 
Berry  dry,  densely  glandular-bristly.      Common    in  southern    Cal- 
ifornia. 

b.  R.    divarica'tum    Dougl.       GOOSEBERRY.     Stems   destitute   of 
prickles  except  on  young  shoots,  with  1-3  thorns  under  each  cluster 
of  leaves.    Calyx  greenish  white  or  purple.     Petals  white,  fan-shaped, 
much  shorter  than  the  filaments  and  2-cleft  style.     Berry  dark  red, 
smooth.     Widely  distributed. 

c.  R.  sanguiVeum  Pursh.     FLOWERING   CURRANT.      Stems  with- 
out prickles  or  thorns,  usually  glandular.     Racemes  numerous,  many- 
flowered,  drooping.     Flowers  rose-color.     Berries  black  or  covered 
with  a  bloom.     This  is  one  of  the  earliest-blooming  plants,  some- 
times flowering  in  November.     The  flowers  appear  before  or  with 
the  leaves,  and  the  whole  plant  is  very  fragrant.     Some  botanists  con- 
sider that  several  species  are  included  in  this.     Widely  distributed. 


DICOTYLEDONOUS  PLANTS  79 

d.  R.  bracteo'sum  Dougl.     Tall  shrub,  without  prickles  or  thorns, 
smooth.     Leaves  sprinkled  with  resinous  dots,  3-9  in.  broad,  5-7- 
cleft,  with  pointed  lobes  and  doubly  serrate  margins  ;  petioles  long. 
Racemes  many-flowered,  becoming  1  ft.  long,  with  persistent  bracts  which 
are  thread-like  above  and  become  leaf-like  below.    Flowers  greenish  white. 
Calyx  saucer-shaped.     Fruit  a  black  berry,  sprinkled  with  resinous 
dots.     Blooming  in  spring  and  found  from  northern  California  to 
Alaska. 

e.  R.  ce'reum  Dougl.     Shrub   with   many  short,  stout  branches, 
which  are  glutinous  and  sprinkled  with  resinous  dots.      Leaves  1  in. 
broad,    kidney-shaped,    5-lobed,  crenately   toothed.     Racemes  with 
3-5  flowers  on  short  peduncles.     Calyx  white,  with  a  greenish  or 
pinkish   cylindrical   tube    £    in.    long,  the   lobes   recurved.     Petals 
orbicular.     Fruit  a  scarlet  berry  with  a  sweet,  resinous  taste.     Blooming 
in  the  spring  and  found  from  northern  California  to  Washington. 

/.  R.  lacus'tre  Poir.  Low  shrub  with  prickly  stems  and  thorns 
under  the  leaf  axils.  Leaves  3-5-parted,  their  lobes  deeply  cut. 
Calyx  saucer-shaped,  petals  small,  stamens  and  style  short.  Fruit 
a  reddish  berry  more  or  less  covered  with  prickles.  From  northern 
California  to  Washington.  The  variety  molle  Gray  is  the  form  com- 
mon in  the  mountains  of  California.  This  species  has  the  fruit  and 
the  prickly  stems  of  the  gooseberry  but  the  racemed  flowers  of  the 
currant. 

VIII.    PHILADEI/PHUS,  Mock  Orange,  Syringa 

Shrubs  with  diffuse  branches,  several  feet  in  height.  Leaves 
opposite,  entire  or  toothed,  ovate  or  oblong,  without  stipules. 
Flowers  showy,  white,  in  paniculate  cymes.  Calyx  with  tube 
adnate  to  the  ovary  almost  to  its  top,  with  J^—5  divisions  which 
are  valvate  in  bud.  Petals  4  or  5,  large,  obovate,  convolute  in 
bud.  Stamens  many,  with  slender  filaments.  Styles  3-5, 
united  at  base  or  almost  to  the  top.  Pod  3-5-celled,  splitting 
from  the  apex  when  ripe,  each  valve  2-parted.  Seeds  many, 
pendent  on  placentae  projecting  from  the  axis. 

a.  P.  Lewis'ii  Pursh.     Nearly   smooth.     Leaves   ovate,    1-2    in. 
long,  nearly  entire.     Panicle  on  a  naked  peduncle.     Styles  distinct  at 
apex  only,  stigmas  narrow.     Blooming  in  spring  and  found  in  the 
Sierra  Nevada  Mountains  from  California  to  British  Columbia. 

b.  P.    Gordonia'nus    Lindl.       Almost   smooth.      Leaves   ovate   to 
oblong,  2-4  in.  long,  coarsely  serrate  with  scattered  teeth.     Flowers 
in  loose  clusters  with  the  peduncles  leafy  at  base.     Styles  distinct  to  the 
middle.     Blooming  in  spring,  in  the  Coast  Mountains,  from  northern 
California  to  Washington. 


80  KEY  AND   FLORA 


IX.    WHIP'PLEA 

Low  shrubs,  with  trailing  stems  and  branches.  Leaves 
opposite,  3-ribbed,  toothed.  Flowers  in  small  cymes  on  slender, 
naked  stems.  Calyx  5-cleft,  with  white  divisions,  the  tube 
attached  to  the  lower  part  of  the  ovary.  Petals  5,  very  small. 
Ovary  3-5-celled,  with  1  seed  in  each  cell.  Styles  as  many  as 
the  cells. 

W.  modes'ta  Torr.  This  is  always  found  in  woods  of  the  Coast 
Mountains,  particularly  in  the  redwoods. 


CALYCANTHA'CE^.  SWEET  SHRUB  FAMILY 

Aromatic  shrubs  with  opposite  leaves  and  no  stipules ; 
sepals,  petals,  and  stamens  passing  into  each  other,  and  all 
uniting  below  into  a  closed  cup  which  is  lined  by  a  hollow 
receptacle  bearing  numerous  simple  pistils. 

Calycan'thus  occidentals  Hook.  &  Am.  SWEET  SHRUB.  Sepals 
numerous,  imbricated,  their  bases  united  in  many  ranks  into  a 
cup-shaped  tube,  the  outer  bract-like,  the  inner  linear-oblong ;  petals 
similar.  Flowers  terminal,  reddish  purple,  fragrant,  with  an  odor  like 
benzoin.  This  grows  near  streams  and  is  more  frequent  in  northern 
California. 

ROSA'CEJE.     ROSE  FAMILY 

Herbs,  shrubs,  or  trees  with  alternate  stipulate  leaves. 
Stamens  numerous,  inserted  on  the  persistent  calyx  or  on  a 
calyx-like  receptacle.  Ovaries  from  one  to  several.  Seeds  few, 
without  endosperm.  This  family  contains  some  of  our  most 
valuable  fruits,  such  as  the  apple,  pear,  quince,  almond,  peach, 
plum,  apricot,  cherry,  raspberry,  blackberry,  and  strawberry. 
There  are  three  great  subdivisions  or  suborders. 

SUBORDER  I.  —  AMYGDA'LEJE 

Trees  or  shrubs.  Fruits  with  a  fleshy  exocarp  enclosing  u 
hard  endocarp,  called  a  drupe  or  stone  fruit  (/.  Fig.  170  ; 
e.  Fig.  180),  as  the  plum,  peach,  almond,  etc. 


DICOTYLEDONOUS  PLANTS  81 


I.    NUTTAI/LIA  (OSMARCXNIA) 

Shrubby,  dioecious.  Flowers  white,  in  drooping  racemes. 
Carpels  5,  usually  only  1  or  2  ripening.  The  stipules  soon 
fall.  The  leaves  when  crushed  have  the  odor  of  bitter 
almonds. 

N.  cerasifor'mis  Torr.  &  Gray.  Oso  BERRY.  Stems  erect,  generally 
growing  in  clumps,  the  male  plants  being  much  more  numerous 
than  the  female,  Racemes  shorter  than  the  leaves,  with  conspicuous 
bracts.  Calyx  broadly  funnel-shaped,  with  a  5-toothed  border.  Petals 
5,  spatulate.  Stamens  15,  10  erect  in  a  line  on  the  calyx,  5  below 
deflexed.  Carpels  on  the  disk  at  the  base  of  the  calyx.  Fruit  black- 
purple,  with  bitter  pulp,  furrowed  slightly  on  the  inner  side.  This 
often  blooms  in  January  in  the  Coast  Mountains,  but  is  much  later 
in  the  Sierra  Nevada.  Widely  distributed. 


II.    PRU'NUS,  Plum,  Cherry 

Trees  or  shrubs.     Flowers  perfect,  white.     Pistil  only  1, 
forming  a  stone  fruit. 

a.  P.   demis'sa  Warp.     CHOKECHERRY.     Trees   or  shrubs   with 
serrate  leaves.     Flowers   in   many-floivered  drooping   racemes.     Fruit 
globose,  red,  or  dark  purple,  astringent.     Widely  distributed. 

b.  P.  ilicifo'lia  Walp.,  ISLAY.     Tree  or  shrub  with  glossy  evergreen, 
spiny,  holly-like  leaves.    Racemes  from  ^  to  2  in.  long.    Fruit  somewhat 
flattened,  £  in.  thick,  sweetish,  the  stone  large  and  the  pulp  thin. 
From  San  Francisco  to  San  Diego. 

c.  P.  emargina'ta  Walp.     Small  tree  with  slender,  reddish  twigs, 
which  are  generally  smooth.     Leaves  obovate  or  oblanceolate,  obtuse 
or  acute,  serrate  with  fine  teeth,  with  2  glands  near  the  summit  of  the 
petiole.     Corymbs  shorter  than  the  leaves,  with  few,  white  flowers.     Fruit 
a  dark  red  cherry,  which  is  bitter  and  astringent. 

d.  P.  Califor'nica  Greene.     Shrub  with  the  branches  from  the  root, 
smooth  and  shining.     Leaves  obovate  to  oblanceolate,  obtuse,  emar- 
ginate,  or  even  acute,  serrate  with  fine  teeth  and  with  1  gland  on  the 
lower  part  of  the  blade.     Flowers  few  in  a  short  corymb:     Fruit  a  red 
cherry,  which  is  very  bitter.     In  the  mountains  throughout  middle 
and  northern  California. 

e.  P.    subcorda'ta  Benth.     Tree  or  shrub  with   thorny  branches. 
Leaves  ovate,  1  in.  long,  with  the  base  wedge-shaped  or  heart-shaped, 
the  margin  finely  and  sharply  serrate.      Flowers  white,  in  few-flow- 
ered umbels.     Fruit  a  red  plum,  £  in.  long,  not  palatable.     This  is 


82  KEY  AND  FLORA 

common  in  the  Coast  Mountains  of  California.  The  variety  Kelloggii 
Lemmon  has  yellow  fruit,  which  is  sweet  and  palatable.  It  is  found 
in  the  northern  Sierra  Nevada  Mountains. 


SUBORDER  IT.  —  RO'SEJE 

Pistils  few  or  many  (sometimes  only  one)  separate  from 
each  other  and  free  from  the  persistent  calyx ;  sometimes,  as 
in  the  rose,  enclosed  and  concealed  in  the  hollow  receptacle. 
Stipules  united  to  the  bottom  of  the  petiole.  Many  are  armed 
with  spines  or  prickles,  and  some  are  valuable  fruits,  as  the 
strawberry,  raspberry,  blackberry. 

I.    NEIL'LIA   (PHYSOCARTUS),  Ninebark,  Bridal  Wreath 

Shrubs  without  thorns  or  prickles,  the  bark  becoming 
shreddy.  Leaves  roundish,  lobed  and  toothed,  with  large 
stipules.  Flowers  in  corymbs  resembling  umbels,  on  short  leafy 
branchlets  disposed  along  the  stems.  Petals  white.  Calyx 
5-lobed.  Stamens  numerous.  Pistils  1-5,  becoming  inflated, 
shining,  2-seeded  pods. 

N.  opulifo'lia  Benth.  &  Hook.  3-10  ft.  high,  the  slender  stems 
often  apparently  climbing  over  the  bushes.  Pods  becoming  reddish 
when  ripe.  Widely  distributed. 

H.    SPIRJE'A,  Hardback 

Similar  to  the  above,  except  that  the  flowers  are  in  com- 
pound corymbs  or  panicles  terminating  the  stems  or  branches,  the 
pods  are  membranous  and  not  inflated,  and  the  leaves  generally 
without  stipules.  Pistils  5,  becoming  several-seeded  follicles. 

a.  S.  densiflora  Nutt.     A  shrub  with  reddish  bark,  leaves  almost 
smooth.     Flowers  rose-purple,  in  compound  corymbs.     In  the  Sierra 
Nevada  Mountains. 

b.  S.  Douglas'ii  Hook.     HARDHACK.     A  shrub  with  reddish  brown 
bark,  leaves  white  on  the  lower  surface,  flowers  rose-purple,  in  panicles, 
stamens  numerous,  giving  the  cluster  a  woolly  appearance.     Northern 
California  to  British  Columbia. 


DICOTYLEDONOUS   PLANTS  83 


III.    HOLODIS'CUS,  Meadow-sweet 

Generally  taller  and  with  small  white  flowers  in  spreading 
panicles.  Stamens  20,  inserted  on  a  disk  like  a  ring.  Pistils 
5,  becoming  1-seeded  carpels  which  are  dehiscent  by  one  side  or 
not  at  all. 

a.  S.  ariaefo'lius.     Shrub  with  dark  brown,  smooth  bark,  leaves 
silky-whitish   beneath,  flowers  white,  turning  brownish,  in  loosely 
flowered  plumose  panicles,  somewhat  drooping  in  flower,  erect  in 
fruit.     Blooming  in  early  summer  and  growing  along  the  woods  of 
the  Coast  Mountains. 

b.  H.  dis'color  Maxim.     Shrub  with  short,  rigid  branches,  clothed 
with  gray-brown,  shreddy  bark.      Leaves   deep  green  and  almost 
smooth  above,  clothed  with  white  tomentum  on  the  lower  surface. 
Panicles  erect  on  short,  erect  branches.    This  is  found  on  the  eastern 
slopes  of  the  Sierra  Nevada  Mountains,  and  north  to  Oregon  and 
Washington. 

IV.    CERCOCARTUS,  Mountain  Mahogany 

Shrubs  or  small  trees.  Leaves  simple,  entire  or  toothed, 
evergreen.  Flowers  axillary,  small.  Calyx  with  a  long  tube 
and  a  saucer-shaped  border.  Petals  absent.  Carpels  included 
in  the  calyx  tube,  usually  1,  tipped  by  a  long,  feathery  style. 

a.  C.  ledifo'lius  Nutt.     Leaves  lanceolate  with  revolute  margins,  thick 
and  resinous,   white-downy   on  the  lower  surface,   smooth    above. 
Flowers  sessile,  downy.    Tail  of  fruit  2  or  3  in.  long.    Chiefly  found 
on  the  eastern  slope  of   the    Sierra   Nevada   Mountains,  north  to 
Oregon  and  Washington.     Spring. 

b.  C.  parvifo'lius  Nutt.     Shrubby,  though  sometimes  15  or  20  ft. 
high.    Leaves  obovate,  wedge-shaped  at  base,  thinner  than  the  preceding, 
with  silky  hairs  above  and  white  down  beneath.     Flowers  on  short, 
slender  pedicels.     Tail  of  fruit  3  or  4  in.  long.     Common,  widely 
distributed,  and  variable.     Spring. 


V.    PURSH'IA  (KUN'ZIA),  Buckbush 

Low,  diffusely  branched  shrubs.  Leaves  in  bunches  on 
the  stem,  wedge-shaped.  Flowers  small,  at  the  ends  of  short 
branchlets.  Calyx  funnel-shaped.  Petals  5,  yellow,  longer 
than  the  calyx  lobes.  Stamens  many,  in  1  row.  Carpels  1 


84  KEY   AND   FLORA 

or  2,  narrowed  at  each  end,  projecting  from  the  calyx,  but  tin 
style  not  becoming  longer  in  fruit. 

P.  tridenta'ta.  Leaves  3-lobed  at  apex,  covered  with  white  down 
on  the  under  surface.  Calyx  also  downy.  This  is  common  in  th^ 
lower  mountains,  especially  on  the^  eastern  side  of  the  Sierra  Nevada 
Mountains.  Late  spring. 


VI.    ADENOS'TOMA,  Chemisal,  Greasewood 

Evergreen  shrub  with  linear,  resinous  leaves.  Flowers 
small,  white,  in  panicles.  Calyx  with  a  10-ribbed  tube  and 
broad,  membranous  lobes.  Petals  5,  round.  Stamens  gen- 
erally from  10  to  15  in  clusters  between  the  petals.  Fruit 
1-seeded,  included  in  the  calyx  tube. 

a.  A.   fascicula'tum   Hook.    &  Arn.      CHEMISAL,    GREASEWOOD. 
Stems  many,  the  slender,  reddish  branches  covered  with  close  clus- 
ters of  very  small,  heather-like  leaves;   stipules  small,  acute.     Flowers 
crowded,  nearly  sessile.     This  often  exclusively  covers  acres,  usually 
growing  on  dry  hills. 

b.  A.   sparsifo'lium   Torr.     YERBA    DEL  PASMO.     Tree  or  shrub 
with  narrowly  linear,  scattered  leaves,  without  stipules.     Flowers  larger 
than  the  preceding,  on  distinct  pedicels.     This  is  found  in  southern 
California.     It  is  very  fragrant,  and  much  used  as  a  remedy  for 
colds  by  the  Indians. 

VH.    GE'UM,  Avens. 

Perennial  herbs.  Leaves  chiefly  radical,  pinnately  divided, 
with  petioles  sheathing  the  stem  and  stipules  attached. 
Flowers  about  as  large  as  a  nickel,  solitary  or  generally  in 
corymbs.  Calyx  open-bell-shaped,  valvate  in  bud,  with  bract- 
lets  between  the  lobes.  Petals  5,  purplish  or  yellow.  Car- 
pels very  numerous,  on  a  dry  receptacle,  the  style  becoming  long  ; 
in  fruit  either  bent  in  the  middle  or  feathery. 

a.  G.  macrophyrium  Willd.    Stems  1-3  ft.  high,  hairy.    Leaves  with 
the  largest  division  at  the  tip.     Corolla  yellow,  with  broad  lobes 
longer  than  the  sepals.     Receptacle  of  the  fruit  smooth.     Styles  bent 
near  the  middle,  the  upper  part  falling,  leaving  the  lower  part  hooked. 
In  the  mountains.     Summer. 

b.  G.  stric'tum  Ait.    Similar  to  the  preceding  but  less  hairy.   Recep- 
tacle of  fruit  downy  instead  of  smooth.     In  the  mountains. 


DICOTYLEDONOUS   PLANTS  85 

c.  G.  riva'le  L.  Somewhat  similar  to  the  preceding  in  habit  of 
growth.  Calyx  brownish  purple.  Petals  purplish,  broad,  with  a 
short  claw.  Style  bent  in  the  middle,  but  the  upper  part  feathery.  In 
the  mountains.  Summer. 

(L  G.  triflo'rum  Pursh  (G.  cilia'tum).  About  a  foot  high.  Leaves  all 
radical,  except  for  a  few  bract-like  leaves  on  the  scapes,  pinnate, 
with  leaflets  crowded  and  irregular  in  size.  Flowers  usually  3,  on 
long  peduncles,  large,  reddish  purple.  Calyx  with  bractlets  longer 
than  its  lobes,  equaling  the  petals.  Styles  straight,  long,  and  feathery. 
Widely  distributed.  Summer. 

Vm.    CHABLZEBATIA,  Mountain  Misery,  Tarweed 

Low,  evergreen,  glandular-aromatic  shrub.  Leaves  tri- 
pinnately  dissected  with  the  ultimate  segments  minute;  stipules 
small,  linear,  entire.  Flowers  about  as  large  as  a  dime,  in 
terminal  cymes.  Calyx  with  top-shaped  tube  and  5-lobed 
border.  Petals  white,  5,  obovate.  Stamens  many.  Pistil 
one  becoming  a  large  akene. 

C.  foliolo'sa  Benth.  This  is  the  only  species.  It  covers  the 
ground  under  the  pines  in  the  Sierra  Nevada  mountains.  Its  fern- 
like  foliage,  strong  odor,  and  abundant  viscidity  cause  it  to  be  well 
known. 

IX.    POTENTIL'LA,  Cinquefoil,  Five-finger 

Herbs  (one  species  shrubby)  with  compound  leaves,  toothed 
leaflets,  and  stipules  attached  to  the  petiole.  Calyx  saucer- 
shaped  or  bell-shaped,  5-cleft  and  with  5  smaller  bractlets. 
Petals  5,  yellow  (rarely  white).  Akenes  on  the  receptacle, 
which  is  dry  and  smooth  or  hairy. 

a.  P.  Anseri'na  L.    SILVERY  CINQUEFOIL.      Stems  prostrate,  with 
runners  like  a  strawberry.     Leaves  pinnately  compound  with   from 
7  to  21  leaflets  (smaller  ones  interposed),  sharply  serrate  and  sil- 
very white  on  the  lower  surface.     Flowers  yellow,  nearly  an  inch 
in  diameter,  petals  falling  easily.     Receptacle  very  woolly.     This 
is  common  in  wet  places  everywhere. 

b.  P.  glandulo'sa  Lindi.     Erect,  a  foot  or  two  high,  covered  with 
glandular   hairs.     Leaves  pinnately  compound  with  from  5   to    7 
leaflets.     Flowers  in  cymes  that  become   open  and  spreading  in  fruit. 
Petals  yellow  or  yellowish  white.     Stamens  25  in  one  row.     This 
usually  grows  in  rather  shady  places.     Widely  distributed. 


86  KEY   AND   FLORA 

c.  P.  gra'cilis  Dougl.  Stems  1-3  ft.  high,  clothed  with  woolly 
hairs.  Leaves  palmately  or  pinnately  compound,  with  7  or  more 
deeply  lobed  or  coarsely  serrate  leaflets  which  are  white-tomentose  on  the 
lower  surface.  Flowers  yellow,  in  loose,  ample  cymes.  Akenes  40 
or  more,  smooth.  This  blooms  in  the  spring  and  is  widely  dis- 
tributed in  the  mountains.  There  are  many  species  very  difficult 
to  distinguish. 

X.    FRAGA'RIA,   Strawberry 

Calyx  5-lobed  and  with  5  alternate  bractlets.  Petals  5, 
white,  spreading.  Stamens  many  in  one  row.  Carpels 
numerous,  on  a  fleshy  receptacle  which  becomes  red  when  ripe, 
and  is  called  the  fruit.  Leaves  palmately  compound  with  3 
toothed  leaflets.  Low  plants,  sending  out  running  stems 
that  root  and  form  new  plants. 

a.  F.  Chilen'sis  Ehr.     COAST  STRAWBERRY.      Leaves  thick,   deep 
green,  glossy  above,  hairy  beneath.     Flowers  white,  an  inch  in  diam- 
eter.    The  fruit  is  delicious,  and  the  akenes  are  in  depressions  on 
the  fleshy  receptacle.     This  usually  grows  on  sandy  hills  near  the 
sea  from  San  Francisco  to  Alaska. 

b.  F.  Califor'nica  Cham.  &  Schl.  *<WooD  STRAWBERRY.     Leaves 
thin,  light  green,  slightly  hairy  on  both  sides.     Flowers  half  an  inch 
in  diameter..    Fruit  small,  with  the  akenes  on  the  surface  of  the 
receptacle,  not  in  depressions.     This  is  generally  found  on  wooded 
slopes  of  the  Coast  Mountains. 

XI.    RU'BUS,  Raspberry 

Calyx  persistent,  5-lobed,  without  bractlets.  Petals  5,  gen- 
erally conspicuous.  Stamens  numerous,  carpels  numerous  on 
a  conical  receptacle,  each  becoming  a  tiny,  round  stone  fruit. 
Leaves  simple  or  compound,  with  stipules  adnate  to  the 
petiole. 

a.  R.  Nutka'nus  Moc.     THIMBLE-BERRY,   SCOTCH  CAPS.      Erect 
shrub  with  large,  5-lobed  leaves,  which  have  gland-tipped  hairs  on 
the  veins  beneath  and  on  the  leafstalks.     Flowers  white  or  pale  rose- 
color,  an  inch  or  more  in  diameter.     Fruit  red,  shaped  like  an  inverted 
saucer,  sweet  and  rather  dry.     From  middle  California  to  Alaska. 

b.  R.  specta'bilis    Pursh.    SALMON-BERRY.      Erect   shrubs   with 
leaves  generally  compound  with  3  leaflets,  the  veins  and  leafstalks 
somewhat  woolly.     Flowers  solitary,  crimson,  less  than  an  inch   in 
diameter.     Fruit  red  or  salmon-color,   thimble-shaped,  pleasant  to  the 
taste.     From  near  San  Francisco  to  Alaska. 


DICOTYLEDONOUS   PLANTS  87 

c.  R.  vitifo'lius  Cham.  &  Schl.     BLACKBERRY.     Stems  trailing, 
very  prickly.    Leaves  compound  with  3-5  leaflets  ;  the  veins  beneath, 
the   leafstalks,   peduncles,   and   sepals   prickly.     Flowers    white,    a 
half  inch  in  diameter.     Fruit  black  when  ripe,  oblong,  sweet.     Widely 
distributed. 

d.  R.  leucoder'mis  Dougl.     Shrub  with   ascending  and  recurved 
stems,   3-5  ft.   long,  pale  green,  prickly.     Leaves  with  3-4  leaflets, 
which  are  ovate-lanceolate,  pointed  and  doubly  serrate,  pale  green  on  the 
lower  surface.     Flowers  few.     Sepals  narrowed  to  a  long  point,  sur- 
passing the  white  petals.     Fruit  black,  generally  covered  with  a  bloom. 
This  is  found  from  northern  California  to  Washington. 

XH.    RO'SA,  Wild  Rose 

Prickly  and  thorny  shrubs.  Leaves  pinnately  compound, 
leaflets  serrate,  stipules  adnate  to  the  petiole.  Receptacle 
globose,  contracted  at  the  throat.  Calyx  of  5  divisions,  with- 
out bractlets.  Petals  5,  rose-color.  Stamens  many,  near  the 
mouth  of  the  receptacle. 

a.  R.  Califor'nica  Cham.  &  Schl.     Stems  with  stout  recurved  thorns. 
Leaflets  2-3  pairs.     Flowers  in  corymbs  or  rarely  solitary.     Fruit 
generally  with  a  distinct  neck  beneath  the  spreading  calyx  lobes. 
This  is  widely  spread  throughout  California,  usually  growing  near 
streams. 

b.  R.   gymnocar'pa  Nutt.     REDWOOD   ROSE.     Slender  shrub  cov- 
ered with  numerous  straight  prickles.     Flowers  generally  solitary, 
less  than  an  inch  in  diameter.     Calyx  lobes  generally  falling  from 
the  fruit.     Pedicels,  petioles,  and   stipules  glandular.     This   dainty 
rose    grows   in    the    shade   of   trees  or   bushes,  usually  under  the 
redwoods. 

SUBORDER  III.  —  POMEJE 

Trees  or  shrubs  with  stipules  not  attached  to  the  petiole. 
Carpels  2-5,  enclosed  in  and  attached  to  the  fleshy  recep- 
tacle, becoming  a  fruit  like  an  apple,  of  which  the  core  is  the 
ovary,  and  the  fleshy  part  the  receptacle  (pome).  Ovules 
2  in  each  cell. 

I.    AMELAN'CHIER,  Service  Berry,  June  Berry 

Shrub  or  small  tree  with  deciduous  leaves.  Flowers  large, 
white,  in  racemes.  Ovary  5-celled,  becoming  a  part  of  the 


88  KEY   AND   FLORA 

berry-like    calyx,   each    cell  partially   divided   by    a  partition 
from  the  back,  1-seeded. 

A.  alnifo'lia  Nutt.  Leaves  rounded,  serrate  towards  the  apex. 
Petals  narrowly  oblong,  nearly  an  inch  in  length.  Fruit,  when 
ripe,  purplish,  edible.  Rather  widely  distributed  and  variable. 

II.     CRAT^'GUS,  Thorn  Apple 

Trees  or  shrubs,  with  thorny  branches.  Leaves  simple, 
toothed  or  lobed.  Flowers  white,  in  corymbs.  Calyx  tube 
urn-shaped,  with  a  5-parted  border.  Corolla  of  5  white, 
spreading  petals,  about  half  an  inch  long.  Stamens  5-20. 
Ovary  2-5-celled.  Fruit  containing  2  or  3  bony  seeds,  either 
separated  or  united. 

C.  Douglas'ii  Lindl.  Tree  10-25  ft.  high,  with  thorns  on  the 
stems  1  in.  long.  Leaves  broadly  ovate,  l£-3  in.  long,  lobed  or 
cleft  and  finely  serrate.  Corymb  with  many  flowers.  Fruit  sweet 
and  insipid,  black.  This  blooms  in  the  spring  and  is  found  from 
northern  California  to  Washington. 


in.    HETEROME'LES   (PHOTIN'IA),  Toyon',  Christmas  Berry 

Shrub  with  evergreen,  oblong,  serrate  leaves  and  minute 
stipules.  Flowers  white  in  close  panicles  at  the  ends  of  the 
branchlets,  fragrant  with  a  sweet,  sickening  odor.  Receptacle 
adnate  to  the  ovary,  becoming  fleshy  in  fruit  and  nearly  cover- 
ing the  2  carpels,  which  are  generally  1-seeded. 

H.  arbutifolia  Rcemer.  Berries  scarlet  with  mealy  pulp,  slightly 
astringent,  but  edible.  In  bloom  chiefly  in  July  and  August ;  in 
fruit  in  November  and  December.  Common  in  the  Coast  Moun- 
tains. 

IV.    PY'RUS  (MA'LUS),  Pear,  Apple 

Trees  or  shrubs,  with  deciduous  leaves  which  are  simple 
or  pinnately  compound,  serrate.  Flowers  in  corymbs,  white 
or  pink.  Calyx  top-shaped  with  the  border  5-cleft.  Petals 
5,  spreading.  Stamens  20.  Styles  5,  more  or  less  united  at 
base.  Fruit  a  pome,  the  5  cartilaginous  carpels  forming  the 
core,  and  the  calyx  tube  becoming  a  fleshy  covering. 


DICOTYLEDONOUS   PLANTS  89 

P.  rivula'ris  Dougl.  Tree  15-25  ft.  high.  Leaves  simple,  ovate- 
lanceolate,  acute  or  pointed,  1-3  in.  long,  sometimes  lobed  or  with 
sharp  teeth  on  the  margins.  Corymb  somewhat  like  a  raceme. 
Pedicels  slender,  1  in.  long.  Petals  orbicular,  white,  ^  in.  long. 
Fruit  reddish  or  yellowish,  ^  in.  long.  This  is  found  from  northern 
California  to  Washington. 

V.     SOR'BUS,  Mountain  Ash,  Rowan 

Shrubs  or  trees.  Leaves  large,  pinnately  compound,  with 
oblong,  serrate  leaflets.  Flowers  small,  white,  in  terminal, 
compound  cymes.  Styles  distinct,  as  many  as  the  cells  of 
the  ovary.  Fruit  about  the  size  of  a  pea,  red  when  ripe, 
usually  containing  one  seed. 

S.  occidentals  Greene.  Shrub  2-6  ft.  high,  smooth.  Leaflets 
3-5  pairs.  Cyme  small,  with  few  flowers.  Fruit  pear-shaped. 
This  grows  in  the  Sierra  Nevada  Mountains,  chiefly  northward. 


LEGUMJNO'S^.     PULSE  FAMILY 

Ovary  1-celled ;  fruit  a  legume  (/.  Fig.  271,  II ;  e.  Fig.  176). 
Leaves  alternate,  compound,  with  stipules  (with  a  few  excep- 
tions). There  are  three  subdivisions,  of  which  two  are  well 
represented  in  California. 

SUBORDER  I.  —  PAPILIONACE^,  PEA  FAMILY 

Calyx  of  5  sepals,  more  or  less  united,  often  somewhat 
irregular.  Corolla  of  5  petals,  papilionaceous  (/.  Fig.  141; 
e.  Fig.  119).  Stamens  10,  either  monadelphous,  diadelphous, 
or  distinct.  Seeds  1  or  several,  without  endosperm. 

I.    THERMOP'SIS,  Golden  Pea 

Herb  with  spreading  underground  stems.  Leaflets  3, 
palmate,  with  stipules  almost  as  large.  Flowers  large,  yel- 
l»tr,  in  terminal  many-flowered  racemes  on  short  pedicels 
with  bracts.  Stamens  distinct  from  each  other.  Legumes 
linear,  compressed. 


90  KEY  AND  FLORA 

a.  T.  Califor'nica  Wats.     Silky-tomentose.      Leaflets   an   inch  or 
two  long,   obovate  ;  stipules  ovate   or  lanceolate,   often  longer  than 
the  petioles.     Pods  1-2  in.  long,  erect  and  slightly  spreading,  with 
but   few   seeds  maturing.      This  is  the  common   species   in  Cali- 
fornia.    It  grows  among  the  hills  of  the  Coast  Mountains  where 
the  ground  is  wet  but  not  marshy,  and  blooms  in  spring. 

b.  T.  monta'na  Nutt.     Silky-hairy.     Leaflets  oblong,  1-3  in.  long ; 
stipules  ovate  or  lanceolate,  generally  longer  than  the  petioles.     Pods 
strictly  erect,    2-3  in.  long.     This  is  found  in   the   mountains    of 
Washington  and  Oregon.     It  blooms  in  the  spring. 

II.    PICKERIN'GIA  (XYLOTHER'MIA),  Spiny  Chaparral,  Chaparral 
Pea,  Needle  Bush 

A  very  spiny  glaucous  shrub  with  small  evergreen  leaves. 
Leaflets  from  1  to  3,  without  stipules.  Flowers  large,  soli- 
tary, nearly  sessile  in  the  axils  of  the  leaves,  of  a  rich  crimson 
color.  It  fruits  very  rarely. 

P.  monta'na  Nutt.  This  is  the  only  species.  It  is  the  most  diffi- 
cult chaparral  of  all  to  penetrate  because  of  its  stout  spines.  It  is 
found  on  dry  hills  in  the  Coast  Mountains. 


HI.    LUPFNUS,  Lupine,  Sun  Dial 

Calyx  generally  2-lipped.  Corolla  with  broad  standard 
and  wings  united  above,  enclosing  the  incurved,  pointed  keel. 
Stamens  monadelphous  in  2  sets.  In  the  bud  one  set  has  long 
anthers,  the  others  are  shorter  and  tipped  with  a  yellow  ball. 
As  the  flower  develops,  the  ball-tipped  filaments  grow  longer 
and  push  the  pollen  up  to  the  top  of  the  keel,  from  which 
the  pistil  projects.  Leaves  palmately  compound,  with  the 
leaflets  folding  at  mid-day.  Stipules  adnate  to  the  petiole. 
Flowers  in  terminal  racemes,  sometimes  arranged  in  whorls 
on  the  peduncles.  The  flowers  are  generally  blue  ;  but  white 
and  yellow-flowered  species  exist,  also  one  combining  yellow 
and  rose-color. 

a.  L.  Chamisso'nis  Esch.  Shrubby,  pale  green  from  the  close 
white  pubescence.  Leaflets  7-9,  silky  on  both  sides.  Flowers 
somewhat  whorled,  blue,  violet,  rarely  white.  This  is  variable,  and 
several  species  have  been  included  under  this  name;  but  they  are 
not  easily  denned.  Throughout  California. 


DICOTYLEDONOUS   PLANTS  91 

b.  L.  arbo'reus   Sims.      Shrubby,  4-10  ft.  high.      Leaflets  7-11, 
generally  9.     Flowers  generally  yellow,  in  whorls,  fragrant.     This 
grows  on  sand-hills  along  the  coast,  where  it  is  abundant  and  very 
showy  in  summer. 

c.  L.  trunca'tus  Nutt.    Annual,  erect,  simple  or  branching  above, 
finely  pubescent,   becoming  smoothish.     Leaflets  5-7,   linear-wedge- 
shaped,  with  the  apex  obtuse,  truncate,  3-toothed  or  entire.    Flowers  small, 
deep  purple,  rather  scattered  on  the  elongating  raceme.     Pods  more 
than  an  inch  long.     Common  in  southern  California.     Spring. 

d.  L.    latifo'lius  Agardh.      Perennial,    stout,    branching,    2-4  ft. 
high,  leafy,  dark  green.     Leaflets  5-7,  oblanceolate,  1-2  in.  long. 
Racemes  long  on  slender  peduncles.     Flowers  rarely  whorled,  violet- 
blue,  turning  brownish  in  fading.    This  is  a  common  species  in  shady 
places  of  the  Coast  Mountains.     Spring. 

e.  L.  microcar'pus  Sims.     Annual,  with  many  spreading  branches 
from  near  the   base,  woolly  throughout.      Leaflets  9,  1  in.  long  or 
more,  narrowly  obovate.     Racemes  containing  many  whorls  of  pur- 
plish flowers  and  persistent  bracts.     Peduncles  short,  stout,  some- 
what succulent,  often  horizontal,  and  with  the  whorls  turned  to  the 
upper  side.     Flowers  rather  large,  on  short  pedicels.     Pods  thick, 
2-seeded.     This  is  common  throughout  California. 

/.  L.  densiflo'rus  Benth.  This  is  very  similar  to  the  preceding, 
but  is  stouter  and  more  spreading,  less  hairy,  with  the  racemes  on 
long  peduncles  and  the  flowers  white  or  yellowish,  rarely  rose-color. 
This  also  is  common  and  widely  distributed. 

(There  are  many  other  species  not  so  readily  recognized 
from  descriptions,  and  many  of  them  are  quite  local.) 

IV.    TRIFO'LIUM,  Clover 

Low  herbs  with  palmately  compound  leaves  of  8  leaflets, 
stipules  adnate  to  the  petiole.  Flowers  in  close  head-like 
clusters  on  axillary  peduncles.  Calyx  with  5,  nearly  equal 
teeth.  Petals  with  claws  attached  to  the  tube  of  the  fila- 
ments. Stamens  usually  diadelphous  (9  and  1).  Legumes 
small,  from  1  to  6  seeded,  usually  enclosed  in  the  calyx.  The 
species  are  numerous  and  difficult. 

V.    MELILO'TUS,  Sweet  Clover 

Leaves  pinnately  compound  of  3  toothed  leaflets.  Flowers 
small,  in  slender  racemes.  Legumes  roundish,  1  or  2  seeded. 


92  KEY  AND  FLORA 

The   entire   plant  is   very  fragrant.      The   two    species    are 
introduced. 

a.  M.  Ind'ica  Allioni.     Flowers  yellow,  common. 

b.  M.  al'ba  Lam.     Flowers  white.     Less  common. 

VI.    MEDICA'GO,  Bur  Clover,  Alfalfa 

Leaves  pinnately  compound,  of  3  leaflets.  Flowers  in  small 
clusters  or  racemes  in  the  axils  of  the  leaves.  Legumes  curved 
or  curled  like  a  screw.  The  species  are  introduced  and  are 
valuable  as  fodder. 

a.  M.  denticula'ta  Willd.    BUR  CLOVER.    Annual,  low,  with  stems 
spreading    on    the   ground,    smooth    throughout.      Flowers    small, 
yellow.     Pod  coiled,  armed  with  a  double  row  of  prickles.     Common. 

b.  M.    sati'va  L.    Alfalfa,    Lucerne.      Perennial,    erect,    smooth. 
Flowers    violet    in    a    close    raceme.       Pod    spirally    coiled,    without 
prickles.     Usually  escaped  from  cultivation. 

c.  M.  apicula'ta  Willd.     This  is  similar  in  appearance  to  M.  den- 
ticulata,  but  the  pods  have  the  margins  rough  with  fine  tubercles  instead 
of  with  hooked  prickles,  and  the  whole  surface  veiny.     In  some  places 
this  is  more  common  than  M.  denticulata. 


VII.    HOSACK'IA  (LOTUS> 

Stamens  diadelphous  (9  and  1).  Petals  with  long  claws, 
free  from  the  stamens.  Leaves  pinnately  compound  with 
from  2  to  many  leaflets.  Flowers  solitary  or  in  umbels,  ses- 
sile or  on  peduncles  from  the  axils  of  the  leaves.  Legumes 
linear,  sessile,  somewhat  compressed  between  the  seeds. 

a.  H.  Purshia'na  Benth.     Annual,  erect  or  spreading  loosely  over 
the  ground,  with  numerous  slender  branches,  soft  woolly  through- 
out.    Leaflets   generally   3    on  a  linear   rhachis.     Flowers  solitary, 
salmon-color,  axillary  on  slender  peduncles  which  are  longer  than  the 
leaves,  with  a  single  lea/let  below  the  Jlower.     Legumes  from  1  to  1£ 
in.  long.     This  is  common,  blooming  in  the  summer  and  autumn. 
Widely  distributed. 

b.  H.  subpinna'ta  T.  &  G.     Sterns  low,  spreading  or  erect,  smooth 
or  woolly.     Leaflets  small,  3-5,  on  a  dilated  rhachis :  stipules  gland- 
like.     Flowers  small,   nearly   or  quite   sessile  in   the  leaf  qxils,  without 
bracts.      Pod  ^  in.   or  more   in  length  with  about  5  seeds.     From 
Santa  Barbara  to  Washington,  common. 


DICOTYLEDONOUS  PLANTS  93 

c.  H.  parviflo'ra   Benth.     Annual,    with    slender,    smooth   stems. 
Leaflets  3-5.     Flowers  very  small,  yellow,  but  becoming  red  with  age : 
peduncles    thread-like,    each   with    a   1-3-leaved   bract.      Pods    linear, 
contracted  between  the   seeds ;  these  5-7.      This  is  common  from 
middle  California  to  British  Columbia.     Spring. 

d.  H.  gra'cilis  Benth.     Perennial   with  slender    stems,    generally 
spreading  over  the   ground  and  growing  in  wet  places.      Leaflets 
5-7 ;    stipules  thin.     Umbels  with   8-10  flowers  about  as  long  as 
the  leaves,  with   a  3-leaved  bract.     Calyx  teeth  snorter  than  the 
tube.     Corolla  with  yellow  banner,  rose-red  wings  and  keel.  -  Pods  long 
and  straight.     This  is  the  most  beautiful  species,  and  it  is  found 
from  Monterey  to  Washington. 

e.  H.  bi'color  Dougl.     Perennial  with  smooth,  erect,  rather  stout 
stems.    Leaflets  5-7,  obovate  or  oblong;  stipules  papery,  rather  large. 
Peduncles  longer  than  the  leaves;   umbel. of  3-7  flowers,  with  or 
without  a  bractv-  Flowers  nearly   sessile,  yellow,  or  with  white  tvings. 
Calyx  teeth  half  as  long  as  the  tube.     This  grows  in  wet  ground 
and  is  found  from  near  San  Francisco  to  Washington. 

/.  H.  gla'bra  Torr.  Somewhat  .shrubby,  tenth  many  nearly  smooth, 
erect,  or  decumbent,  stems  from  the  root.  Leaves  few,  with  3  small 
leaflets.  Umbels  numerous,  sessile  along  the  stem,  consisting  of  many 
yellow  flowers  that  become  reddish.  Legumes  curved  and  tipped  with 
the  long  style.  This  is  common  all  over  the  state,  and  in  bloom  at  all 
seasons.  There  are  many  other  species  more  difficult  to  distinguish. 

VIII.     PSORA'LEA 

Ill-scented  herbs  covered  ivith  dark,  glandular  dots.  Leaves 
with  3-5  leaflets  and  stipules  free  from  the  petiole.  Flowers 
white  or  purplish  in  axillary  spikes  or  racemes,  ivith  thin 
bracts  that  soon  wither  and  fall.  Legumes  sessile,  1-seeded, 
indehiscent. 

a.  P.  orbicula'ris  Lindl.  Stems  running  along  the  ground  in  swampy 
places,  bt  tiring  leaves  and  spikes  of  flowers  on  petioles  and  peduncles  a 
foot  or  more  long.  Leaflets  large,  round.  Flowers  large,  purple,  in 

close,  woolly  spikes.     Stamens  diadelphous  (9  and  1).     Throughout 

California. 

b,  P.  macrosta'chya  DC.      Stems  usually  very  tall,  6  ft.   or   even 
more.    Leaves  ovate-lanceolate.    Peduncles  much  longer  than  the  leaves. 
Spikes   silky-woolly,    with    blackish    hairs   on   the   calyx.      Bracts 
broad.     Corolla   purple.      The    tenth   stamen    almost  free.     Legumes 
woolly.     Throughout  California,  along  streams. 

r.  P.  physo'des  Dougl.      f/rww////  a  foot   or  tiro  high,  with  serera) 
front    the    base.      Flowers   in    short,    close   racemes. 


94  KEY   AND   FLORA 

Calyx  becoming  slightly  inflated  in  fruit.  Corolla  yellowish  wJiite, 
tinged  with  purple.  Stamens  monadelphous.  In  the  Coast  Moun- 
tains from  Monterey  County  to  Puget  Sound. 

IX.    ASTRAGALUS,  Rattleweed,  Loco-weed 

Herbs  with  odd-pinnate  leaves  and  numerous  leaflets. 
Flowers  in  racemes  or  spikes,  on  axillary  peduncles.  Stamens 
diadelphous  (9  and  1).  Keel  of  'the  corolla  blunt  at  tip. 
Legumes  numerous,  more  or  less  ^-celled  by  one  or  both  sutures 
projecting  inwards,  often  inflated  like  a  bladder  so  as  to  secure 
dispersion  of  the  seed  by  the  wind.  Several  species  are  poison- 
ous to  cattle  and  sheep.  Almost  all  are  perennials.  The 
species  are  numerous  and  too  difficult  for  beginners. 

X.    VIC'IA,  Vetch 

Vines,  with  the  leaves  terminating  in  tendrils.  Stipules  semi- 
sagittate.  Flowers  solitary  or  in  loose  axillary  racemes.  Sta- 
mens diadelphous.  Stigma  a  round  hairy  ball  at  the  tip  of  the 
slender  style.  Legumes  similar  to  those  of  the  common  pea. 

«.  V.  gigante'a  Hook.  Perennials,  stout,  climbing  high  over  the 
bushes.  Leaflets  from  10  to  1 5  pairs.  Corollas  reddish  or  dirty  white, 
turning  brown.  Pods  becoming  black  wlien  ripe,  each  seed  encircled  by  its 
stalk.  This  is  common  in  moist  places  from  San  Francisco  northward. 

b.  V.  America'na  Muhl.  PEA  VINE.  Perennial,  generally  low. 
Leaflets  from  4  to  8  pairs,  linear,  generally  truncate  or  toothed  at 
apex.  Flowers  bluish,  in  few-flowered  racemes.  Legumes  smooth. 
Seeds  3-6,  dark  purple.  Widely  distributed. 

XI.    LATH'YRUS,  Wild  Pea  ^v 

-       •  & 

This  is  similar  to  Vicia,  except  that  the  tendrils  are  absent 
in  some  species,  the  flowers  are  larger,  the  leaflets  broader, 
and,  most  important,  the  style  is  hairy  not  only  at  the  tip, 
but  also  down  the  inner  side. 

The  species  are  difficult  to  distinguish. 

SUBORDER  II.  —  CJESALPIN'EJE 

Flowers  more  or  less  irregular.  Corolla  not  truly  papilio- 
naceous, with  the  petal  that  answers  to  the  standard  folded 


DICOTYLEDONOUS   PLANTS  95 

within  those  on  the   side.     Stamens  10  or  fewer,  distinct. 
Seeds  sometimes  with  endosperm. 

CER'CIS,  Red-bud,  Judas-tree 

A  small  tree  or  shrub,  blooming  before  the  leaves  appear. 
Leaves  cordate  to  kidney-shaped,  entire,  palmately  veined. 
Flowers  bright  rose-color,  in  axillary  clusters,  numerous  on  the 
leafless  stems.  Petals  5,  the  standard  enclosed  by  the  wings. 
Pod  large,  flat  and  thin,  turning  purplish. 

C.  occidentals  Torr.  This  is  the  only  native  species  on  the 
Pacific  Coast.  It  is  most  beautiful  along  mountain  streams  through- 
out California,  but  not  near  the  seacoast. 

SUBORDER  III.  —  MIMO'SE^E 

Flowers  regular,  small,  and  numerous  in  spikes  or  heads. 
Calyx  and  corolla  of  4  or  5  divisions.  Stamens  as  many  or 
twice  as  many  as  the  petals,  or  numerous,  inserted  on  the 

receptacle. 

ACA'CIA 

Flowers  small,  numerous  in  spikes  or  heads.  Stamens  very 
numerous.  Flowers  usually  yellow  (rarely  rose-color). 

Leaves  various,  naturally  pinnately  compound,  but  in  many 
Australian  species  reduced  to  a  petiole  flattened  and  broad- 
ened like  a  leaf  (phyllodia).  On  young  plants  the  gradations 
between  the  compound  leaf  and  the  simple  phyllodia  can 
often  be  seen. 

GERANIA'CE^.     GERANIUM  FAMILY 

Herbs  with  pungent,  acid,  or  aromatic  juice.  Sepals  and 
petals  5.  Stamens  5  or  10. 

The  fruit  consists  of  5  distinct  carpels  around  a  central 
column,  or  is  a  5-10-valved  capsule  splitting  so  as  to  shoot 
out  the  seeds. 

I.     GERA'NIUM,  Crane's  Bill 

Annual  or  perennial  herbs  with  large  joints  and  palmately 
lobed  leaves,  stipules  papery.  Style  5-lobed  at  the  summit. 


96  KEY  AND  FLORA 

Fruit  of  5  carpels,  which  separate  when  ripe  from,  the  axis, 
each  one  ivith  a  long,  beardless  tail,  which  curls  from  the  bot- 
tom of  the  axis  to  the  summit.  Most  of  the  plants  cultivated 
as  geraniums  belong  to  the  genus  Pelargonium. 

a.  G.  inci'sum  Nutt.     Perennial,  with  branching,  leafy  stems,  with 
glandular  and  hairy  pubescence.     Flowers  large,  axillary,  on  pedicels 
that  are  spreading  or  reflexed  in  fruit.     Petals  purple,  woolly  on  the 
inner   surface.     Filaments  woolly.      Fruit    with    the   beak  glandular. 
Common  in  the  Sierra  Nevada  Mountains  and  extending  to  Wash- 
ington and  Oregon.     It  blooms  in  spring  and  summer. 

b.  G.  Richardson'ii  F.  &  M.     This  is  somewhat  similar  to  the 
preceding,  and  like  it,  is  perennial.     The    stems    are   taller,  more 
slender,  and  weaker.     The  flowers  are  smaller,  and  always  white, 
though  there  may  be  pink  veins  on  the  petals.     It  grows  in  wet 
places  in  the  mountains  at  rather  high  elevations. 

c.  G.  Carolinia'num  L.     Annual,  with  spreading  stems,  and  gray, 
somewhat   glandular    pubescence.     Flowers   and  leaves   closely  clus- 
tered at  the  ends  of  branchlets,  the  former  small,  rose-color,  the  latter 
orbicular  in  outline,  but  cut  into  several  divisions.     Carpels  covered 
with  black  hairs,  beak  woolly  or   glandular.     Common  and  widely 
distributed. 

d.  G.  dissec'tum  L.     Greener   than  the  preceding,   and    with  the 
leaves  cut  into  narrower  and  more  numerous  divisions.     Stems  weak, 
often    supported   on  other  plants,  and  frequently  growing   in  wet 
places.     Common,  introduced. 

H.    ERO'DIUM,  Alfilerilla,  Filaree' 

This  is  similar  to  Geranium;  but  the  filaments  are  broader, 
and  those  opposite  the  petals  are  without  anthers,  the  tails 
of  the  carpels  are  bearded  on  the  inner  side,  and  when  they 
break  away  from,  the  axis  they  form  a  spiral.  The  flowers 
are  usually  in  umbels  with  an  involucre  of  4  bracts,  and  the 
petals  are  small  and  fall  easily. 

a.  E.  cicuta'rium  L'Her.  RED-STEMMED  FILAREE.  Leaves  form- 
ing a  rosette  at  the  base  of  the  stem,  compound  with  many  leaflets, 
which  are  cut  into  numerous,  narrow,  acute  lobes ;  the  stem  leaves 
are  small,  and  shorter  than  the  peduncles.  Flowers  rose-purple, 
4-8  in  an  umbel.  The  axis  on  which  the  carpels  are  arranged  is 
from  1  to  2  in.  long.  This  is  the  commonest  and  most  valued 
"  filaree." 


DICOTYLEDONOUS  PLANTS  97 

b.  E.  moscha'tum  L'Her.    GREEN-STEMMED  FILAREE.     This   has 
a  faint  odor'  of  musk.     The  root  leaves  form  a  cluster,  but  are  larger 
and  coarser  than  the  preceding,  and  erect,  often  a  foot  long.     The 
leaflets  are  doubly  serrate.     This  always  has  a  greener  and  more 
luxuriant  appearance  than  the  preceding.     Widely  distributed. 

c.  E.  Bo'trys  Bert.     Stems  short,  depressed.     Leaves  in  a  rosette, 
reddish  and    shining,  oblong  in    outline  with  coarsely-toothed  seg- 
ments.    Petals  lilac-purple,  longer  than  the  calyx,  forming  a  bell- 
shaped   corolla.     Carpels  with   beaks  2-4  in.  long.     This  gives  a 
reddish  color  to  the  hills  along  the  seaboard  in  early  spring.     The 
long  beaks  of  the  akenes  are  conspicuous  later.     It  is  introduced, 
and  likely  to  be  found  everywhere  along  the  coast. 

d.  E.  macrophyllum  H.  &  A.     Stems  very  short,  glandular-hairy 
above.     Leaves,  kidney-shaped,  crenate-serrate.     Petals  white,  as  long 
as  the  sepals.     This  is  found  chiefly  in  clayey  soil,  and  is  widely 
distributed. 

m.    LIMNANTHES,  Meadow  Foam 

Smooth,  succulent  annuals  ivith  pungent  juice.  Leaves 
alternate,  without  stipules,  pinnately  cleft.  Flowers  showy, 
solitary,  on  axillary  peduncles,  white,  yellowish,  or  rose- 
color.  Petals  convolute  in  the  bud.  Stamens  10.  Carpels 
at  first  fleshy,  becoming  hard  and  wrinkled,  separating  from 
the  short  axis.  This  grows  always  in  wet  places. 

a.  L.    Douglas'ii  R.  Brown.     Stems   very   smooth,  brittle,  much 
branched.     Peduncles  2-4  in.  long.     Sepals  lanceolate,  petals  twice 
as  long,  yellow,  white,  or  of  both  colors,  obovate,  emarginate.     This 
beautiful    plant   sometimes   covers   large   areas    in    wet    meadows. 
Throughout  California. 

b.  L.  ro'sea   Hartw.     Leaves   with   narrow  linear  lobes;    flowers 
white,  turning   rose-color.     This  is  found  in  the  great  valleys  of 
California. 

c.  L.    al'ba   Hartw.     Short  and  stout,    with   the   leaf   segments 
broad,    short,    3-lobed.     Petals   white,  not   much   longer  than   the 
densely  woolly  sepals.     Northern  California. 

IV.    OX'ALIS,  Wood  Sorrel 

Low  herbs  with  acid  juice,  often  without  a  stem.  Leaves 
compound  with  8  obcordate  leaflets,  like  clover.  Stamens  10, 
with  filaments  dilated  and  united  at  the  base.  Capsule 
beaked  with  the  short  style,  5-celled  with  the  valves  remain- 
ing attached  to  the  axis  by  -the  partitions. 


98  KEY  AND  FLORA 

a.  0.  Orega'na  Nutt.     WOOD  SORREL.     Perennial  herbs  forming 
mats,  with  slender  rootstocks  from  which  arise  the  leaves  and  flow- 
ering stems.    Leaflets  broadly  obcordate,  rusty  underneath.     Scapes 
usually  1 -flowered,  with  2  bracts  near  the  flower.     Petals  nearly  an 
inch  long,  pink,  white,  or  rose-color  with  darker  veins.     This  is  common 
in  the  redwood  forests  of  the  coast,  north  to  Washington. 

b.  0.  cornicula'ta  L,   YELLOW  SORREL.   This  also  often  forms  mats 
with  slender  prostrate  stems.     Leaflets  deeply  obcordate.     Peduncles 
bearing  2  or  more  flowers  with  yellow  petals.     The  reddish-leaved,  yel- 
low-flowered sorrel,  which  is   a  common  weed  in  the  streets  and 
gardens,  is  a  variety  of  this  species. 


LINA'CEJE.     FLAX  FAMILY 

Flowers  with  all  parts  5,  except  the  pistil.  Sepals  per- 
sistent, imbricated.  Petals  convolute  in  the  bud,  falling 
soon.  Each  division  of  the  ovary  contains  a  pair  of  seeds. 

LFNUM,  Flax 

Herbs  with  tough  fibers  in  the  bark.  Leaves  sessile,  entire. 
Styles  2-5.  Ovary  globose,  with  as  many  true  cells  as  styles, 
each  cell  partially  separated  into  two  false  cells.  The  cap- 
sule splits  through  the  false  and  true  partitions,  each  half 
cell  containing  one  seed.  The  species  are  rather  local  and 
with  one  exception  small-flowered. 

L.  Lewis'ii  Pursh.  Perennial,  with  erect,  leafy  stems,  smooth 
and  bluish  green.  Leaves  generally  linear,  an  inch  or  less  long, 
without  stipules.  Flowers  azure  blue,  nearly  an  inch  in  diameter, 
in  racemes  or  corymbs  on  elongating  pedicels.  Pod  longer  than 
the  calyx,  10-celled  and  10-valved,  with  the  valves  widely  spreading 
when  ripe.  Common  and  widely  distributed,  blooming  in  spring 
and  summer. 

The  introduced  flax,  L.  usitatis'simum  L.,  is  somewhat  similar, 
but  is  an  annual.  There  are  many  small-flowered,  annual  species 
in  California,  but  they  are  difficult  to  distinguish  and  are  more  or 
less  local. 

POLYGALA'CE,®.     POLYGALA  FAMILY 

Herbs  or  shrubs  with  simple,  entire  leaves  without  stipules. 
Flowers  superficially  resembling  a  pea  blossom.  Stamens 


DICOTYLEDONOUS   PLANTS  99 

united   into  one  or  two  sets,  adnate  to  the  petals;  anthers 
1-celled,  opening  at  the  top. 

POLYG'ALA 

Sepals  5,  two  of  them  large  and  spreading  like  wings. 
Petals  3,  united  to  each  other  and  to  the  stamen  tube,  the 
middle  one  forming  a  hood.  Stamens  6-8,  with  filaments 
united  into  a  tube,  split  down  one  side.  Pod  notched,  flat- 
tened contrary  to  the  partition,  2-celled,  with  one  seed  in 
each  cell. 

a.  P.    cornu'ta   Kellogg.      Low   shrub   with   slender   stems   and 
branches,   1-6  ft.  high.     Leaves  oval,   obtuse,  on  very  short  peti- 
oles.    Flowers  greenish  white  tinged  with  rose-color,  in  short  racemes. 
Outer  sepals  usually  finely  tomentose.     Petals  shorter  than  the  keel, 
which  is  tipped  with  a  straight  beak.     Pod  orbicular  with  the  apex 
notched.    This  grows  in  the  pine  woods  through  the  Sierra  Nevada. 

b.  P.  Califor'nica  Nutt.     Low  perennial  with  slender,  woody  stems 
rising  2-8  ft.  from  creeping  rootstocks.  Flowers  in  terminal  racemes. 
Sepals  nearly  smooth.     Petals  purple,  with  the  wings  longer  than 
the  keel,  which  has  a  recurved  beak.      The  fruit  is  chiefly  from  flowers 
without  petals  near  the  root.    The  pod  is  smooth  and  almost  orbicular. 
This  is  common  in  the  Coast  Mountains  of  California  and  extends 
to  Oregon. 

EUPHORBIA'CE^.     SPURGE  FAMILY 

Herbs  with  milky  juice  which  is  sometimes  poisonous. 
Leaves  simple  with  stipules.  Flowers  monoecious  or  dioe- 
cious, naked  or  apetalous.  Stamens  1  to  many.  Pistil  1, 
with  a  3-lobed  ovary  and  6  styles  or  stigmas.  Pod  dehiscing 
with  an  elastic  movement  that  scatters  the  seeds,  leaving 
the  axis. 

I.    EUPHOR'BIA,  Spurge,  Milkweed 

Flowers  monoecious,  both  the  staminate  and  the  pistillate 
included  in  a  cup-shaped  involucre  which  might  be  mistaken 
for  a  calyx.  Staminate  flowers  numerous,  each  of  a  single 
stamen  on  a  short,  jointed  pedicel  with  a  tiny  bract  at  base. 
Pistillate  flowers  solitary,  hanging  on  a  long  pedicel  from  the 
center  of  the  involucre.  Ovary  with  one  ovule  in  each  cell ; 


100  KEY   AND   FLORA 

styles  3,  each  with  2  stigmas.  Involucre  4-5-lobed,  the  lobes 
alternating  with  crescent-shaped  or  colored  and  petal-like 
glands. 

a.  E.  albomargina'ta  Torr.  &  Gray.     Stems  numerous,  forming  a 
prostrate    mat.     Leaves   small,  almost   round,   cordate  with  a  narrow 
whitish  edge.     Stipules  united  into  a  triangular,  white,  membranous 
scale.   Glands  of  the  involucre  4,  brownish  orange  with  white  or  rose- 
color,  petal-like  appendages  with  entire  margins.     Seeds  4-angled. 
This  grows  in  southern  California. 

b.  E.    serpyllifolia    Pers.     Annual   with   prostrate   or   ascending 
stems,  smooth.     Leaves  with  the  base  unequal,  oblong,  1-6^-  in.  long, 
the   margins  with  some  very  fine    teeth.       Stipules   bristle-like    or 
ragged.     Involucres  generally   solitary.     Seeds  4-angled,  somewhat 
pitted.     The  glands  are  small  and  the  margins  narrow,  whitish,  cre- 
nate.     This  is  widely  distributed  and   is  often  found  along  roads 
and   railroad   tracks.       It   blooms    in    summer    and   turns   reddish 
towards  fall. 

c.  E.  crenula'ta  Engelm.     Annual  or  biennial,  erect  with  one  or 
several  leafy  stems  from  the  root,  generally  branching  above  with 
2-forked  branches.     Leaves   about  an  inch  long,  spatulate.     Invo- 
lucres with  crescent-shaped  glands  and  no  petal-like  appendages.     Seeds 
gray,  covered  with    dark-colored   pits.     This  blooms   early  and  is 
widely  spread. 

H.    EREMOCAR'PUS,  Turkey  Mullein,  Yerba  del  Pescado 

Stems  branched  from  the  base,  prostrate,  forming  a  mat. 
Flowers  monoecious,  clustered  in  the  axils  of  the  leaves 
without  an  involucre.  Staminate  flowers  with  a  5  or 
6  parted  perianth  ;  pistillate  flowers,  naked.  Capsule  1-celled 
and  1-seeded. 

E.  setig'erus  Benth.  Grayish  green,  covered  with  white  hairs 
and  a  stellate  pubescence.  Leaves  3-nerved,  ovate,  obtuse,  round 
at  base,  on  long  petioles.  Flowers  inconspicuous.  This  is  called 
"  turkey  mullein "  because  turkeys  are  fond  of  the  seeds.  The 
name  given  by  the  early  settlers  is  "  yerba  del  pescado "  because 
it  was  used  by  the  Indians  in  catching  fish.  The  effect  of  the 
leaves  thrown  into  a  fish  stream  is  to  stupefy  the  fish  so  that  they 
can  be  caught  by  hand.  Common  in  middle  California  and  inclined 
to  cover  waste  places.  Summer  and  fall. 


DICOTYLEDONOUS   PLANTS  101 


ANACARDIA'CE^.     POISON  OAK  FAMILY 

Shrubs  or  trees  with  leaves  alternate,  without  stipules, 
either  simple  or  compound.  Flowers  small,  regular.  Stamens 
inserted  on  the  inner  margin  of  the  disk.  Ovary  1-celled, 
1-ovuled.  Styles  often  3.  Fruit  a  small  drupe. 

RHUS,  Sumac,  Poison  Oak 

Sepals  and  petals  (4-9)  generally  5.  Stamens  as  many 
or  twice  as  many.  Sterile  and  fertile  flowers  often  mixed  in 
the  clusters.  Only  the  first  species  is  poisonous. 

a.  R.    diversilo'ba   T.    &   G.     POISON  OAK.     Stems   shrubby  or 
climbing  by   rootlets.      Leaves  compound   with  3  leaflets,   which    are 
3-lobed  and  coarsely  toothed  or  entire.     Flowers  yellowish  white,  fra- . 
grant,  in  loose  panicles  in  the  axils  of  the  leaves.     Fruit  a  round, 
white,  nerved,  smooth  berry.     This  is  most  poisonous  in  the  spring. 
It  generally  forms  thickets.     The  foliage  turns  red  in  the  fall. 

b.  R.  triloba'ta  Nutt.     SQUAW  BUSH,  INDIAN  LEMONADE.     An 
aromatic  shrub  with  numerous,  spreading  branches.     Leaves  some- 
what variable,  with  3  leaflets,  the  middle  one  3-lobed  and  toothed, 
much  larger  than  the  2   side  leaflets,  which   are  generally  simple 
and    crenate.      Flowers   greenish,   in  short  spikes,   which  precede  the 
leaves.     Fruit  a  red  berry,  pleasantly  acid.     Seeds  white  and  smooth. 
Widely  distributed,  but  not  especially  common. 

c.  R.  integrifolia  Benth.  &  Hook.     Shrub  or  small  tree.     Leaves 
many,  evergreen,  thick,  oval,  entire  or  with  spiny  teeth,  dark  green 
and  glossy  above,  sometimes  compound.     Flowers  rose-color,  in  clus- 
tered spikes.     Fruit  covered  with  an  acid,  viscid  coat ;  the  berry  about 
£  in.  long.     This  is  found  in  southern  California  near  the  sea. 

d.  R.  ova'ta  Wats.     Similar  to  the  above,  but  with  larger,  thin- 
ner leaves,  which  are  ovate  or  almost  heart-shaped ;  fruit  having  the 
viscid  coat  crusted  with  a  white  powder.     This  is  found  in  the  moun- 
tains of  southern  California. 

e.  R.  lauri'na  Nutt.     Shrub  with  oblong-lanceolate,  entire  leaves 
on  rather  long  petioles.     Flowers  many  in  a  terminal  panicle,  small, 
white.     Fruit  smooth,  whitish,  beaked  by  a  stout  style.     This  grows  in 
southern  California  near  the  coast. 

Schi'nus  mol'le  L.  PEPPER  TREE.  This  is  extensively  cultivated. 
It  is  an  evergreen  tree,  with  graceful,  drooping  branches  and  com- 
pound leaves,  with  20  or  more  pairs  of  narrow  leaflets.  The  flowers 


102  KEY   AND   FLORA 

are  small,  dioecious,  in  large  panicles,  with  5  greenish  petals  and  10 
stamens.  The  fruit  consists  of  numerous  pungent  rose-color  drupes 
as  large  as  dry  peas. 

SAPINDA'CEM  (including  BUCKEYE  and  MAPLE) 

Trees  or  shrubs  with  deciduous  simple  or  compound  leaves 
without  stipules.  Sepals  5,  often  irregular,  and  more  or  less 
united.  Petals  alternate  with  the  sepals  or  wanting.  Stamens 
more  than  5.  Ovary  with  2  ovules  in  each  cell,  often  only 
one  maturing. 

I.    -ffiS'CULUS,  Buckeye 

Leaves  opposite,  palmately  compound,  of  5-9  leaflets. 
Flowers  white  or  pale  rose-color,  in  a  panicle  nearly  a  foot 
long;  very  few  are  fertile,  the  majority  being  staminate. 
Calyx  tubular.  Petals  4  or  5,  with  long  claws.  Ovules  6, 
2  in  each  cell  of  the  ovary ;  but  generally  only  one  ripening, 
becoming  a  large  chestnut-like  seed  which  is  covered  with  the 
three  leathery  valves  of  the  capsule.  The  abortive  seeds  can 
all  be  seen  within  the  capsule. 

M.  Califor'nica  Nutt.  This  is  a  low-spreading  tree  or,  rarely,  a  shrub. 
The  leaves  fall  very  early,  leaving  the  pods  hanging  on  long,  naked 
peduncles.  Rather  widely  distributed  through  middle  California. 

II.    AC'ER,  Maple 

Trees  or  shrubs  with  deciduous  palmately  lobed  leaves. 
Petals  as  many  as  the  sepals,  and  inserted  with  the  sta- 
mens on  the  margin  of  the  disk.  Fruit  of  2,  winged  carpels. 

a.  A.  macrophyllum  Pursh.    LARGE-LEAVED  MAPLE.    This  grows 
to  be  a  large  tree  with  leaves  from  6  in.  to  nearly  a  foot  broad. 
Flowers    yellowish,    fragrant,    in  drooping    racemes.       Fruit    densely 
hairy,  with  wings  obliquely  spreading.     This  grows  along  streams. 
From  Santa  Barbara  to  British  Columbia. 

b.  A.  circina'tum  Pursh.    VINE  MAPLE.    Shrubs  or  small  trees  with 
trailing  stems  that  strike  root  where  they  touch  the  ground,  forming 
thickets.  Flowers  in  loose,  umbel-like  corymbs.  Fruit  smooth,  with  wings 
horizontally  spreading.     Northern  California  to  British  Columbia. 


DICOTYLEDONOUS   PLANTS  103 


III.    NEGUN'DO,   Box  Elder 

A  small  tree,  with  leaves  pinnately  compound  with  3  leaf- 
lets. Flowers  dioecious,  apetalous.  Staminate  flowers  in 
umbels  with  very  slender  pedicels.  Fertile  flowers  in  droop- 
ing racemes,  Fruit  of  2,  winged  carpels  with  wings  almost 
parallel. 

N.  Califor'nicum  Torr.  &  Gray.  This  grows  along  streams  in  the 
Coast  Mountains,  but  is  not  very  abundant. 


RHAMNA'CEJE.     BUCKTHORN  FAMILY 

Shrubs  or  trees  with  simple  leaves  and  small  flowers. 
Calyx  valvate  in  the  bud.  Stamens  opposite  the  petals. 
Ovary  with  from  2  to  4  cells.  Stigmas  with  as  many  lobes 
as  there  are  cells  to  the  ovary.  Seed  solitary  in  each  cell. 

I.    RHAM'NUS,  Coffee  Berry,  Cascara  Sagrada 

Leaves  alternate,  with  stipules  that  soon  fall.  Calyx  tube 
urn-shaped  with  a  4  or  5  cleft  margin.  Petals  very  small  or 
none.  Ovary  a  drupe  containing  2  or  3  stones. 

a.  R.  cro'cea  Nutt.     Leaves  evergreen,  almost  orbicular,  small,  shin- 
ing above,  inclined  to  be  yellow  beneath,  sharply  toothed.     Flowers  with 
the  parts  in  fours.     Berries  red.     Throughout  California. 

b.  R.  Califor'nica  Esch.     Leaves  evergreen,  1-4  in.  long,  £-2  in. 
wide,  elliptical,    denticulate,  or  nearly  entire.      Fruit  black-purple, 
^-seeded.     Throughout  California. 

c.  R.  Purshia'na  DC.     This  sometimes  becomes  a  tree.     Leaves 
deciduous,  elliptical,  pubescent  beneath,  2-7  in.  long,  1-3  in.  wide. 
Petals  cleft  at  the  apex.     Fruit  black,  3-seeded.     This  is  more  com- 
mon in  northern  California  and  extends  to  British  Columbia. 

II.    CEANO'THUS,  California  Lilac 

Trees,  or  more  often  shrubs,  with  small,  simple  leaves. 
Flowers  small,  blue  or  white,  in  cymes  or  panicles.  Calyx 
bell-shaped,  with  colored  margin.  Petals  with  a  small  claw, 
the  blade  forming  a  hood.  Ovary  half  immersed  in  the  disk, 


104  KEY  AND   FLORA 

style  3-cleft.  Fruit  a  3-seeded  capsule  embraced  at  the  base 
by  the  calyx  tube,  dehiscent  from  the  junction  of  the  3  cells 
with  elasticity  sufficient  to  scatter  the  hard  nutlets. 

a.  C.  thyrsiflo'rus  Esch.     BLUE-BLOSSOMS.     A  tall  shrub  or  tree 
with  small  alternate  leaves,  3-nerved  from  the  base.     Flowers  dense 
in  numerous,  compound  racemes,  often  forming  a  thyrse,  light  blue,  very 
fragrant.     This  is  one  of  the  most  beautiful  plants  when  i 

It  frequently  covers  places  where  the  redwoods  have  been 
burned.     From  Monterey  County  northward. 

b.  C.  veluti'nus  Dougl.     This  is  a  stout,  diffusely  branched  shrub. 
Leaves  alternate,  large,  thick,  resinous,  and  shining  on  the  upper  surface, 
aromatic,  strongly  ribbed  from  the  base.    Floivers  white,  in  loose  clusters 
on  short  peduncles.     Common  in  northern  California  and  Oregon. 

c.  C.  integer'rimus  H.  &  A.     Tall,  erect  shrub  without  spines. 
Leaves    alternate,   3-nerved,   ovate,   soft-hairy   on  both  surfaces,  on 
short  petioles.     Flowers  wJiite  or  blue  in  slender  panicles.     Pods  nearly 
smooth  with  the  crests  on  the  sides.     Through  California  in  the  moun- 
tains, to  Washington.     In  some  places  it  is  known  as  red-root. 

d.  C.    divarica'tus  Nutt.       Tall   shrub    with    olive    or    bluish-green 
branchlets.     Leaves  alternate,  ovate,  3-nerved,  colored  like  the  twigs 
but  with  the  upper  surface  darker.     Flowers  pale  blue,  in  ample  pani- 
cles.     Pods  smooth,  scarcely  crested.     The  stems  are  rigid  and  fre- 
quently spiny.     This  is  common  in  southern  California. 

*e.  C.  inca'nus  T.  &  G.  Shrub  with  stiff,  spiny,  diffusely  branched 
stems.  Leaves  alternate,  large,  elliptical  to  ovate,  pale  green,  1-2^  in. 
long.  Flowers  in  short,  dense,  axillary  clusters,  frequently  forming 
a  thyrse.  Pod  very  resinous,  lobed  at  top.  This  is  found  in  the 
Coast  Mountains  of  middle  California. 

f.  C.  cordula'tus    Kellogg.      SNOW-BUSH.     Low  shrubs,  generally 
with  flat    tops ;  stems  with  spreading   branches   gray  or   glaucous. 
Leaves  alternate,  elliptical  to  orbicular,  generally  obtuse  at  base,  den- 
ticulate at  apex,  pale  gray-green  on  the  lower  side,  darker  above. 
Flowers  white,  small,  in  numerous  small  clusters  all  over  the  stems. 
Capsules  smooth,  slightly  crested.     This  forms  thickets  in  the  moun- 
tains of  California  and  Oregon. 

g.  C.    folio'sus   Parry.       Low   shrub   with    declined    or    trailing 
branches.     Leaves  alternate,   small,  ivith  glandular,  revolute   margins. 
Flowers  dark  blue  or  rarely  white,  in  small,  numerous  clusters  all 
over  the  stems.      This  blooms  profusely  soon  after  the  rains  and  is 
in  bloom  almost  continually.     Common  in  the  Coast  Mountains. 

h.  C.  soredia'tus  H.  &  A.  Erect  shrub,  becoming  tree-like,  with 
spreading,  rigid  branches,  somewhat  thorny.  Leaves  alternate,  ellip- 
tical, glandular  on  the  margins,  gray-green  on  the  lower  surface,  darker 
above.  Flowers  deep  blue,  small,  in  very  numerous,  small,  oblong 


DICOTYLEDONOUS   PLANTS  105 

clusters.     This    is  found  in  the  Coast  Mountains,  and    is  a  most 
beautiful  sight  in  full  bloom. 

i.  C.  cunea'tus  Nutt.  Widely  branched  with  rigid  branchlets.  Leaves' 
opposite,  spatulate  or  wedge-shaped,  on  very  short  petioles,  paler  on  the 
lower  surface  in  lines.  Flowers  in  small  umbels  which  are  close 
together  on  the  branches,  white  or  lavender.  Pods  with  3  erect 
horns  or  crests.  This  is  common  throughout  California  to  Oregon. 
^^^^L  crassifolius  Torr.  Erect  shrub  with  rigid  branches,  the 
«|  ^Bwigs  clothed  with  white  down.  Leaves  opposite,  thick,  white- 
^on  the  lower  surface,  obtuse  or  retuse  at  apex.  Flowers  in  numer- 
ous clusters  on  short  peduncles,  light  blue  or  white,  very  densely 
clustered.  Capsule  with  3  horn-like  crests  below  the  summit.  This  is 
found  in  the  Coast  Mountains,  especially  in  southern  California. 

k.  C.  pineto'rum  Coville.  Low  shrubs  with  flat  tops  and  many 
stiff,  spreading  branches.  Leaves  opposite,  thick,  glossy  on  the  upper 
^surface,  coarsely  toothed.  Flowers  blue  or  white,  rather  large,  in 
many  small  clusters.  Capsules  large,  red,  with  large,  erect  horns  near 
the  apex  and  with  crests  between.  On  dry  hills  in  the  Sierra  Nevada 
and  Coast  Mountains. 

/.  C.  prostra'tus  Benth.  SQUAW-CARPETS,  MAHALA  MATS.  Stems 
forming  mats,  rooting.  Leaves  opposite,  thick,  with  sharp  teeth  on 
the  margins,  spatulate  or  wedge-shaped.  Flowers  blue,  rather  large. 
Pods  large,  red,  with  3  large,  wrinkled  horns  at  the  apex  and  crests 
between.  Common  in  the  mountains  of  California  and  extending 
to  Washington. 

MALVA'CEJE.     MALLOW  FAMILY 

Herbs  or  shrubs  with  flowers  generally  showy.  Calyx  with 
lobes  valvate  in  the  bud,  often  with  an  outer  row  of  bracts 
below,  resembling  another  calyx.  Petals  5,  united  at  the  base 
of  the  stamen  tube.  Stamens  numerous,  united  into  a  column 
by  their  filaments,  enclosing  the  pistils.  Anthers  kidney- 
shaped,  1-celled,  except  in  Fremontia.  Fruit  a  3-10-celled 
pod  or  a  cluster  of  one-  to  several-seeded  carpels,  at  the  base 
of  the  united  styles,  commonly  called  "  cheeses." 

I.    LAVA'TERA,  Tree  Mallow 

Stout  shrubs,  frequently  planted  as  wind-breaks.  Leaves 
large,  evergreen,  5-7-lobed.  Flowers  axillary,  on  long  pedun- 
cles. Calyx  with  an  outer  row  of  3-6  leaflets.  Carpels  1-seeded. 


106  KEY   AND   FLORA 

L.  assurgentiflo'ra  Kellogg.  This  grows  to  a  height  of  several  feet, 
and  has  large  reddish  purple  flowers,  veined  with  darker  lines. 

II.    SIDAI/CEA,  Rose  Mallow 

Perennial  or  annual  herbs.  Leaves  round  in  outline,  lobed 
or  parted.  Flowers  rose-color,  in  a  terminal  raceme  or  spike. 
Calyx  with  outer  bracts  wanting.  Column  of  stamens  double. 
Carpels  1-seeded,  indehiscent. 

a.  S.  malvaeflo'ra  Gray.     Perennial  with  several  stems  from  the 
root  1-2  ft.  high,  erect  or  ascending,  hairy.     Root  leaves  rounded, 
deeply  crenate ;    stem  leaves  7-parted,   with   the  divisions   3-lobed. 
Flowers  in  spike-like   racemes,    rose-color.       Carpels   becoming  some- 
what wrinkled  and  veiny  when  ripe.     There  are  two  kinds  of  flowers. 
Those  with    rudimentary   anthers    are   smaller  and  generally  of   a 
deeper  color ;  the  perfect  flowers  are  an  inch  or  more  across.     The 
pistils  ripen  after  the  pollen  is  discharged.     This  is  variable  and 
common  near  the  coast. 

b.  S.  Orega'ng.  Gray.     Perennial.     Stems    solitary    or    few  from 
the  root,  2-6  ft.  in  height,  branching  into  panicles  which   are  stel- 
late  pubescent.      Leaves  chiefly  at  the  base,   orbicular  in  outline, 
7-9-lobed,    the    lobes    cleft.       Flowers    |— 1    in.    long    in    spicate 
racemes.      Carpels  slightly  beaked,   smooth.     From  northern  Califor- 
nia to  Oregon. 

c.  S.  diploscy'pha   Gray.     Annual,  with  hairy  stems  1-2  ft.  high  ; 
branches     spreading.        Leaves    round-kidney-shaped,    the    earliest 
crenate,  the  others  with  5-7  lobed  divisions.     Petals  pink,  an  inch 
long.      Carpels  veiny  and  wrinkled,  depressed,  beakless.     This  is  com- 
mon in  middle  California  in  fields,  growing  like  a  weed.     It  is  one 
of  the  most  beautiful  species. 

III.    MALVAS'TRUM 

Erect  shrubs  or  herbs.  Calyx  with  3  outer  bracts.  Stamen 
tube  simple.  Stigmas  capitate.  Carpels  1-seeded,  usually 
splitting  from  the  top. 

a.  M.  Par'ryi  Greene.  Annual.  Stems  prostrate  or  ascending. 
Leaves  deeply  5-parted,  with  toothed  or  lobed  segments.  Flowers 
axillary,  on  long,  slender  peduncles.  Carpels  15-20.  This  is  sim- 
ilar to  Sidalcea  malvceflora  in  the  dioecious  character  of  its  flowers. 
The  perfect  flowers  are  often  more  than  an  inch  in  diameter. 
This  is  found  in  middle  California  in  dry  places. 


DICOTYLEDONOUS  PLANTS  107 

b.  M.  fascicula'tum  Greene.  A  shrub  6-8  ft.  high,  with  long,  slen- 
der branches.  Leaves  tomentose,  5-lobed,  coarsely  toothed.  Flowers 
in  racemes  or  panicles.  Corolla  rose-purple,  f  in.  long.  •  Carpels 
smooth  below,  tomentose  above.  This  is  a  beautiful  shrub,  or 
sometimes  a  tree,  common  in  southern  California. 

IV.    FREMON'TIA,  Slippery  Elm 

A  shrub  or  small  tree,  with  small  3-7-lobed  leaves,  rusty 
stellate  pubescent.  Calyx  1-3  in.  in  diameter,  5-cleft  almost 
to  the  base,  with  bright  yellow,  leathery  divisions,  imbri- 
cated in  the  bud;  persistent  bractlets  under  the  calyx  3-5, 
small.  Corolla  wanting.  Stamens  5,  with  filaments  united 
to  the  middle.  Anthers  linear,  2-celled.  Capsule  4  or  5 
celled,  dehiscent  from  the  top.  This  is,  by  some  authorities, 
put  into  Sterculiacece. 

F.  Califor'nica  Torr.  FALSE  SLIPPERY  ELM.  This  is  a  fine 
sight  when  in  bloom.  The  large  yellow  flowers  are  numerous  on 
the  long  stems.  The  fruit  is  densely  hairy  and  woolly  on  the 
inside,  and  the  dry  open  pods  persist.  The  bark  is  used  as  slip- 
pery elm.  From  middle  California  to  San  Diego. 


HYPERICA'CE.®,    ST.  JOHN'S-WORT  FAMILY 

Herbs  with  opposite  leaves,  covered  with  transparent  or 
dark  dots  or  with  both  kinds.  Flowers  with  4  or  5  sepals, 
and  as  many  petals.  Stamens  numerous  in  3-5  clusters, 
on  the  receptacle.  Styles  3-5,  more  or  less  united.  Pod 
splitting  at  the  partitions  into  3  valves. 

HYPERI'CUM,  St.  John's-wort 
Flowers  yellow.     Stamens  in  several  sets,  stigmas  capitate. 

a.  H.  Scou'leri  Hook.     Erect,  with  simple  stems  from  running  root- 
stocks.    Leaves  oblong,  obtuse,  clasping,  about  an  inch  long.    Flowers 
nearly  an  inch  in  diameter,  in  panicled  cymes.     This  grows  in  moist 
places,  chiefly  in  the  mountains. 

b.  H.  concin'num  Benth.     Stems  low,  numerous,  from  a  woody  base. 
Leaves  not  clasping,  usually  folded,  growing  in  four  distinct  ranks  up 


108  KEY  AND  FLORA 

the  stem.     Stamens  very  numerous,  in  3  sets.     Corollas  nearly  an 
inch  in  diameter.     This  grows  on  dry  hills  in  central  California. 

c.  H.?  anagalloi'des  Cham.  &  Schl.  Stems  weak,  low,  spreading, 
rooting  at  the  joints,  growing  in  wet  places  and  forming  mats.  Leaves 
small,  clasping.  Flowers  small,  in  cymes.  Pod  1-celled.  Widely 
distributed. 

FRANKENIA'CE^,  YERBA   REUMA   FAMILY 

Low,  spreading,  perennial  herbs  or  shrubs,  with  opposite, 
entire  leaves  and  no  stipules.  Calyx  tubular,  4  or  5  lobed, 
ribbed.  Petals  with  long  claws  inserted  on  the  receptacle. 
Stamens  4-7.  Ovary  1-celled.  Fruit  a  2-4-valved  pod 
included  in  the  calyx  tube. 

a.  Franke'nia  grandiflo'ra  Cham.  &  Schl.    YERBA  REUMA.     Stems 
very  numerous,  slender.     Leaves  numerous,  small  and  narrow,  with 
the  margins  rolled  under.     Petals  small,  pink.     On  account  of  the 
great  amount  of  salt  contained  in  this  plant  it  is  almost  impossible 
to  dry  it.     It  is  common  in  salt  marshes  on  the  coast. 

b.  F.  grandiflo'ra  var.  campes'tris.     This  is  the  form  found  in  the 
interior  alkaline  marshes. 


CISTA'CE^,  ROCKROSE  FAMILY 

Calyx  in  2  series ;  the  outer  sepals  2,  smaller  than  the  3 
inner,  turned  to  the  left  in  the  bud,  while  the  5  petals  are 
turned  to  the  right.  Stamens  many,  style  1.  Fruit  a  cap- 
sule, with  the  parietal  placentae  protruding  towards  the  center. 

HELIAN'THEMUM,  Rockrose 

Perennials,  with  many  slender  steins  about  a  foot  high 
from  a  woody  root.  Flowers  small,  yellow,  open  only  in  sun- 
shine, with  petals  soon  falling.  Ovary  opening  into  3  valves. 

H.  scopa'rium  Nutt.  This  grows  on  dry  hills  throughout  Cali- 
fornia, in  the  Coast  Mountains. 


DICOTYLEDONOUS  PLANTS  109 


VIOLA'CE^,   VIOLET   FAMILY 

Low  perennial  herbs  having  alternate  leaves  with  leaf-like 
stipules.  Flowers  on  axillary  peduncles.  Sepals  5,  persist- 
ent. Petals  5,  one  with  a  spur  at  base.  Stamens  5,  short, 
with  the  filaments  cohering  around  the  pistil.  Style  club- 
shaped,  with  a  one-sided  stigma.  Pod  1-celled,  splitting  into 
3  parts,  each  bearing  seeds  on  the  middle  nerve.  The  seeds 
are  often  scattered  by  the  bursting  of  the  elastic  valves. 

VI'OLA,  Violet 

Sepals  ear-like  at  the  base.  Petals  somewhat  bearded 
within,  thus  affording  a  foothold  for  bees,  the  lowest  one 
with  a  spur  at  base.  Stamens  not  cohering  very  much,  the 
lowest  with  spurs  which  reach  down  into  the  spur  of  the 
lowest  petal. 

a.  V.  palus'tris  L.     Stemless,  low,  from  thread-like  creeping  root- 
stocks.      Leaves  round-cordate,  1-2  in.  in  diameter,  faintly  crenate. 
Flowers  pale  lilac  to  white,  with  short,  rounded,  sac-like  spurs.    Northern 
California  to  Alaska,  growing  in  swampy  places  in  the  mountains. 

b.  V.  cani'na  var.  adun'ca  Gray.     BLUE  VIOLET.     Stems  leafy, 
several   from   the   rootstock.      Leaves  simple,    ovate-cordate,    with 
leaf -like  stipules.     Flowers  blue,  ivith  the  spur  as  long  as  the  sepals. 
The    side   petals    are    bearded.       Widely   distributed    in    the    Coast 
Mountains. 

c.  V.  ocella'ta  T.   &  G.     HEART'S-EASE.    Stems    leafy.     Leaves 
heart-shaped,    crenate,    with    small    papery    stipules.      Upper  petals 
white   within,  dark  on  the  outside;  the  others  pale  yellow,  veined  with 
purple  ;  those  on  the  sides  with  a  purple  spot  near  the  base.     In  woods 
from  Monterey  County  northward. 

d.  V.  peduncula'ta  T.  &  G.      PANSY.     Stems   leafy,  with  ovate 
leaves  wedge-shaped  at  the  base.     Stipules  narrowly  lance-shaped. 
Flowers  large,  on  long  peduncles,  deep  yellow.     Upper  petals  tinged 
with  brown  on  the  outside,  the  others  veined  with  purple,  those  on 
the  sides  bearded.     Common  from  southern  to  middle  California. 

e.  V.    sarmento'sa    Dougl.      CREEPING   VIOLET.      Stems  creeping 
by  leafy  stolons.      Leaves  finely  crenate,  round,  with  heart-shaped 
base.     Flowers  light  yellow.     This  grows  in  the  woods  of  the  Coast 
Mountains. 


110  KEY   AND   FLORA 

f.  V.   praBmor'sa   Dougl.     Stems  short,  frequently  underground, 
gray  pubescent  or  smooth.     Leaves  ovate-lanceolate,  with  the  margin 
sinuate  to  dentate,   tapering  to  the  petiole.     Sepals  papery,  entire  or 
slashed.     Petals  yellow,   generally  tinged   with   brown   on   the   outside. 
Ovary  globular,  pubescent.     Variable  and  widely  distributed. 

g.  V.  loba'ta  Benth.    Stems  leafy.    Leaves  palmately  cut  into  5-9  nar- 
row lobes,  the  central  one  the  longest.     (The  root  leaves  are  sometimes 
simple  with  crenate  margins.)    Stipules  large,  leaf-like.    Flowers  yel- 
low.    Upper  petals  brownish  purple  on  the  outside,  the  others  veined 
or  tinged  with  purple,  the  side  petals  slightly  bearded.     Throughout 
California. 

h.  V.  chrysan'tha  Hook.  Apparently  stemless.  Leaves  round  in 
outline,  twice  divided  into  linear  segments.  Stipules  lance-shape'd. 
Flowers  on  peduncles  as  long  as  or  longer  than  the  leaves,  bright 
yellow.  Lower  petals  veined,  yellow ;  the  upper  brownish  purple  on 
the  outside  ;  the  side  petals  not  bearded.  On  low  hills  from  Monte- 
rey County  northward. 

i.  V.  trinerva'ta  Howell.  Stemless,  smooth.  Leaves  palmately  3-5- 
parted  with  lanceolate,  acute  divisions;  stipules  small,  entire,  almost 
free.  Upper  petals  deep  blue  or  violet :  lower  yellow.  Washington. 

j.  V.  Beckwith'ii  T.  &  G.  Stemless,  hairy  or  almost  smooth. 
Leaves  orbicular,  palmately  3-parted  into  linear,  obtuse  divisions.  Upper 
petals  deep  blue  or  violet,  lower  light  blue  or  white,  with  the  base  yellow- 
ish. This  is  found  from  northern  California  in  the  Sierra  Nevada 
to  Oregon,  generally  on  the  eastern  slope. 


MYRTA'CEJE,  MYRTLE  FAMILY 

EUCALYP'TUS.  There  are  many  different  species  of  this 
genus  cultivated  in  California.  The  young  shoots  have  oppo- 
site leaves  much  broader  than  the  older  leaves,  which  are 
alternate.  The  calyx  never  opens.  It  is  like  a  lid  and  falls 
off.  Under  this  is  another  very  thin  lid  which  answers  to 
the  corolla.  Then  the  numerous  stamens  rise  and  expand, 
producing  a  tassel-like  blossom.  The  fruit  is  a  3-5-celled 
capsule  imbedded  in  the  receptacle  and  opening  by  chinks  at 
the  top.  The  commonest  species  in  cultivation  is  the  Blue 
Gum,  Eucalyptus  globulus  Labill. 


DICOTYLEDONOUS  PLANTS  111 


ONAGRAXCE.5£,  EVENING  PRIMROSE  FAMILY 

Herbs  with  the  calyx  tube  inserted  on  the  ovary.  Parts 
of  the  flower  4,  except  the  stamens,  which  are  generally  8. 
Capsule  4-celled,  and  stigma  4-lobed  or  capitate.  Leaves 
simple,  without  stipules.  Flowers  usually  showy. 

I.    ZAUSCHNE'RIA,  Wild  Fuchsia 

Perennial  herbs  with  many  low  ascending  stems  from 
woody  rootstocks.  Leaves  opposite,  except  the  upper  ones. 
Flowers  large,  scarlet,  in  racemes.  Calyx  with  tube  globose 
just  above  the  ovary,  the  funnel-formed  border  4-lobed,  with  8 
scales  within,  4  erect  and  4  deflexed.  Petals  4,  obcordate  and 
deeply  cleft,  a  little  longer  than  the  calyx  lobes.  Stamens  8 
in  2  sets,  one  shorter  than  the  other.  Anthers  versatile. 
Stigma  4-lobed  or  shield-shaped.  Pod  4-angled.  Seeds  with 
a  tuft  of  down  at  the  end. 

Z.  Califor'nica  Presl.  All  the  forms  of  Zauschneria  are  considered 
by  many  botanists  to  belong  to  this  species.  It  is  extremely  vari- 
able, and  found  through  California ;  blooming  from  summer  until 
late  in  the  fall. 

H.    EPILO'BIUM,  Willow  Herb 

Perennial  herbs  often  growing  near  water.  Calyx  with 
tube  short  or  none,  border  with  4  spreading,  deciduous  lobes. 
Petals  spreading  or  erect,  purplish  or  white,  often  notched  at 
the  apex.  Stamens  8  in  2  sets,  one  shorter ;  anthers  versa- 
tile. Stigma  with  4  spreading  lobes  or  somewhat  club- 
shaped.  Pod  4-sided.  Seeds  with  a  tuft  of  long  white  hairs. 

a.  E.  spica'tum  Lam.  FIREWEKD.  Perennial,  with  tall,  erect, 
simple,  leafy  stems.  Leaves  sessile,  lance-shaped,  entire.  Flowers 
reddish  purple,  large,  in  a  long  spike  tritti  noticeable  bracts.  (The 
spike  resembles  a  raceme  because  of  the  long,  linear  ovaries,  which 
look  like  pedicels.)  Style  yellow,  hairy  at  the  base,  with  4  linear 
stigma  lobes.  This  is  common  in  the  Sierra  Nevada  Mountains 
wherever  the  timber  has  been  burned,  and  also  in  the  northern 
part  of  the  Coast  Mountains. 


112  KEY   AND   FLORA 

b.  E.  panicula'tum    Nutt.     Annual,  with    slender   stems    branching 
widely  above,  low  or  10  ft.  high.     Leaves  small,  often  in  clusters  on 
the   main  stem,  almost  wanting  on  the  branches.     Flowers  small, 
rose-color,  veined  with  darker  lines,  terminating  the  slender  thread- 
like branches.     Petals  deeply  notched,  nearly  twice  as  long  as  the 
calyx   lobes.     This    is   common,  and   blooms   in  the  fall.     Widely 
distributed. 

c.  E.    adenocau'lon   Hausskn.      Stems   ascending,   tall,   with   the 
inflorescence  branched.     Leaves  ovate-lanceolate,  with  rounded  base, 
finely  toothed  margins,   and  short-winged  petioles.     Flowers  small, 
rose-color,  nodding  at   first.     Inflorescence    and   seed-pods  glandular 
pubescent.     This  is  common  and  widely  distributed.     It  grows  near 
wet  places.     Little  rosettes  of  leaves  appear  late  in  the  season  at  the 
base  of  the  stem. 

m.    (ENOTHE'RA,  Evening  Primrose 

Herbs  with  alternate  leaves.  Flowers  various,  with  calyx 
tube  prolonged  above  the  ovary,  and  the  lobes  reflexed,  often 
remaining  somewhat  united.  Petals  4,  white  or  yellow,  turn- 
ing reddish  or,  in  some  yellow-flowered  species,  greenish. 
Stamens  8,  with  anthers  versatile.  Stigma  either  with  4 
linear  divisions  or  capitate.  The  following  are  the  most 
widely  distributed  species. 

a.  (E.  Califor'nica  Watson.    WHITE  EVENING  PRIMROSE.    Peren- 
nials,  with  low,   rather   stout   stems   covered    with    white,   shining 
epidermis.     Flowers  axillary,  with  petals   white,  obcordate,  more  than 
an  inch  long.     Style  4-cleft.     Capsules  2  in.  long,  slightly  tapering. 
Central  and  southern  California. 

b.  CE.  bien'nis  L.     YELLOW   EVENING   PRIMROSE.     Stem  erect, 
often  3  ft.  high,  leafy.      Flowers  large  (often  more  than  2  in.  in  diam- 
eter), yellow,  in  a  leafy  spike.     Stigmas  with  4  linear  lobes.     This 
is    generally  found  in   moist   places.     There   are   several  varieties, 
diifering  chiefly  in  the  amount  of  pubescence  and  the  size  of  the 
flowers.     Widely  distributed. 

c.  (E.  gauraeflo'ra  T.  &  G.    NODDING  EVENING  PRIMROSE.    Stems 
leafy,  simple  or  branched  from  the  base.     Flowers  rather  small  (not 
£  in.  in  diameter),  very  numerous,  white,  turning  rose-color,  in  a  nodding 
spike.     Capsules  slender,  linear,  much  contorted.     This  is  common 
in  the  San  Joaquin  Valley  on  the  sides  of  hills  or  gulches. 

d.  (E.  ova'ta  Nutt.     SUN   CUPS  (incorrectly   called  COWSLIPS). 
Low,  with  leaves  and  flowers  from  a  fleshy  root  forming  rosettes  on  the 
ground.     Leaves  broadly  lance-shaped,  with  the  margins  generally 
toothed  or  wavy,  3-8  in.  long,  often  the  midvein  red.     Calyx  tube 


DICOTYLEDONOUS  PLANTS  118 

like  a  long  stem,  1-4  in.  long,  extending  down  to  the  capsule,  which 
is  underground.  Corolla  bright  yellow,  with  petals  ^  in.  or  more  long. 
Stigma  capitate.  This  grows  in  moist  places  not  far  from  the  coast, 
and  blooms  early. 

e.  CE.  campes'tris  Greene.  Annual,  with  many  slender  branches 
from  the  root,  6  in.  to  nearly  a  foot  high.  Leaves  narrow,  linear,  den- 
tate. Calyx  tube  short,  funnel-form,  attached  to  the  long  linear 
capsule,  which  often  becomes  somewhat  contorted.  Petals  £  in.  or 
less  long,  bright  yellow,  sometimes  spotted  at  base.  Anthers  versatile, 
stigma  capitate.  This  is  generally  many-flowered,  and  is  quite  com- 
mon south  of  San  Francisco. 

/.  (E.  cheiranthifolia  Hornemann.  Stems  decumbent,  often  2  ft.  or 
more  long,  white,  with  a  close  pubescence,  especially  on  the  younger  parts. 
Leaves  oblanceolate  to  ovate,  the  upper  sessile.  Ovary  and  calyx 
woolly.  Petals  yellow,  generally  turning  greenish  when  withering.  Pods 
angled,  becoming  contorted.  This  is  common  on  the  sands  along 
the  coast,  chiefly  south  of  San  Francisco,  and  is  quite  variable. 


IV.    GODE'TIA,  "Farewell  to  Spring" 

Calyx  tube  prolonged  beyond  the  ovary,  funnel-shaped, 
with  reflexed  lobes  somewhat  united,  deciduous.  Petals  4> 
generally  rose-color,  often  marked  with  spots  of  deeper  color. 
Stamens  8  in  2  sets,  one  shorter 'than  the  other,  and  ripen- 
ing earlier ;  anthers  attached  at  the  base.  Stigmas  4,  gen- 
erally purple.  Capsule  4-celled.  The  following  species  are 
the  most  easily  distinguished  and  most  common. 

a.  G.   lep'ida  Lindl.     Annual,  erect  herbs   with   white,  shining 
stems.     Flowers  in  spikes.      Tips  of  the  calyx  lobes  free  in  the  bud. 
Petals  rose-color,  with  a  darker  spot  near  the  top.       Capsule  with  a 
single  row  of  seeds  in  each   cell,  sessile,  narrowed  towards  the  apex, 
ribbed,  white-hairy.     Monterey  County  to  Oregon. 

b.  G.  amce'na  Lilja.     Stems  loosely  branching  below,  with  widely 
spreading  branches.     Flowers  nodding  in  the  bud,  large  and  showy 
(an  inch  or  more  in  diameter).     Petals  white,  rose-color,  or  purple, 
with  a  darker  spot  at  the  center.     Capsules  narrowed  at  both  ends, 
on  short  pedicels.     From  Monterey  County  northward. 

c.  G.  quadrivurnera  Spach.     Stems  slender,  a  foot  or  two  high. 
Leaves  narrow,  entire  or  slightly  denticulate,  an  inch  or  two  long. 
Tips  of  the  calyx  lobes  slightly  free  in  the  bud.     Petals  purplish,  about 
half  an  inch  long.     Stigma  lobes  short,  purplish.     Capsule  narrowed 
to   the  top,  ribbed   and  hairy.     Seeds  in  one  row  in  each  cell.     This 
species  is  widely  distributed. 


114  KEY  AND  FLORA 

d.  G.  purpu'rea  Watson.    Stems  leafy,  a  foot  or  two  high.    Leaves 
oblong,  entire,  an  inch  or  two  long.     Flowers  in  a  leafy  terminal 
spike.      Tips  of  the  calyx  lobes  not  at  all  free  in  the  bud.     Petals  deep 
purple,  half    an  inch   long.     Stigma  lobes   purple,  short.      Capsule 
ovate  to  linear-oblong,  sessile,  not  ribbed.     Seeds  in  2  rows  in  each  cell. 
From  Oregon  to  Los  Angeles. 

e.  G.   Bot'tae   Spach.     Erect,  with   few   branches,   1-2  ft.   high, 
almost    smooth.     Leaves    linear-lanceolate,   1-2   in.  long,   entire  or 
with  a  few  teeth  on  the  margin.     Petals  light  purple,  about  an  inch 
long.      Pod  narrowed  at  each  end,  about  an  inch  long,  on  pedicels  ^-f 
in.  long.     This  is  common  in  southern  California. 

/.  G.  epilobioi'des  Wats.  Stems  erect,  slender,  one  foot  or  less 
high,  slightly  clothed  with  white  down  or  smooth.  Leaves  linear. 
Petals  pale  rose  or  white,  a  half  inch  or  less  long.  Pod  narrowed  at 
each  end,  an  inch  or  less  long.  Common  in  southern  California. 

V.     CLAR'KIA 

Calyx  tube  prolonged  beyond  the  ovary,  funnel-shaped, 
with  reflexed,  united,  deciduous  lobes.  Petals  4,  with  long 
claws.  Stamens  8  in  2  sets,  those  opposite  the  petals  often 
sterile.  Anthers  attached  by  the  base.  Pods  linear. 

The  chief  difference  between  Clarkia  and  Godetia  consists 
in  the  clawed  petals  of  the  former. 

a.  C.  el'egans  Dougl.     Stems  simple  or  branched,  from  6  in.  to 
6  ft.  high.     Divisions  of  the  calyx  united  except  on  one  side,  deep 
wine-color  on  the  inner  surface.     Petals  reddish  purple,  with  long, 
slender  claws  and  rhomboidal   blades.     Anthers  all  perfect.     Capsule 
nearly  sessile,  often  woolly.     Widely  distributed. 

b.  C.  concin'na  Greene  (Eucharidium).    Stems  slender,  with  spread- 
ing branches.     Calyx  tube  very  slender,  an  inch  long.     Petals  dark 
rose-color,  3-lobed.     Stamens  only  4-     Stigma    lobes    unequal.     Cap- 
sules about  an  inch  long,  sessile.    This  is  a  very  showy  plant,  bloom- 
ing in  summer.     In  the  Coast  Mountains. 

c.  C.    pulchel'la   Pursh.     Stems   branching,  about   a   foot    high. 
Leaves  linear-lanceolate,  1-3  in.  long,  entire,  smooth.     Petals  rose- 
color,  with  3  broad-spreading  lobes,  the  claw  with  a  pair   of  recurved 
teeth.     Perfect  stamens  4,  each  with  a  scale  on  each  side  of  the  base. 
There  are  4  stamens  that  are  rudimentary.     Stigma  lobes  dilated.    Pod 
1   in.  long,  8-angled,  on  spreading  pedicels.     From  northern   Cali- 
fornia to  British  America. 


DICOTYLEDONOUS   PLANTS  115 


LOASA'CEJE.     BLAZING  STAR  FAMILY 

Herbs  covered  with  rough  barbed  hairs.  Calyx  tube  attached 
to  the  1-celled  ovary  with  parietal  placentae.  Stamens  numer- 
ous, merging  into  the  petals. 

MENTZE'LIA,  Blazing  Star 

Tall  and  erect,  or  loosely  branching  herbs,  with  stems  white 
and  shining.  Flowers  showy,  yellow,  orange  or  cream-color ; 
from  very  small  to  3  or  4  in.  in  diameter.  The  barbed  hairs 
cause  the  plant  to  adhere  to  whatever  it  happens  to  touch. 
The  numerous  stamens  and  spreading  petals  give  this  plant  a 
radiant  appearance  like  a  star.  The  species  are  local. 

M.  laevicau'lis  T.  &  G.  Biennial,  with  stout  branching  stems, 
2-3  ft.  high.  Leaves  lanceolate,  2-8  in.  long.  Flowers  sessile  on 
short  branches,  3-4  in.  broad,  light  yellow,  blooming  in  the  morn- 
ing. Calyx  tube  naked.  Petals  5-10.  Stamens  numerous.  This 
is  generally  found  growing  in  the  beds  of  streams  in  the  mountains 
through  California  to  Washington. 

CACTA'CEJE.      CACTUS  FAMILY 

Peculiar  green  fleshy  perennial  plants,  armed  with  bundles 
of  spines,  and  rarely  possessing  leaves.  Flowers  with  numer- 
ous sepals,  petals,  and  stamens,  in  several  series,  forming  a 
cup  above  the  1-celled,  many-ovuled  ovary.  Style  1,  with 
several  stigmas.  Fruit  a  pulpy  or,  rarely,  a  dry  1-celled 
berry  with  numerous  seeds.  The  following  are  the  common 

genera. 

I.    MAMILLA'RIA,  Bird's-nest  Cactus 

Round  or  oval  plants,  covered  with  spine-bearing  tubercles. 
Flowers  small,  arising  between  the  tubercles.  Ovary  naked. 
Seeds  without  endosperm. 

H.    ECHINOCAC'TUS,  Indian  Melon 

Round  or  oval  plants,  usually  ribbed,  with  bundles  of  spines 
on  the  ribs.  Flowers  from  the  youngest  part  of  the  ribs  close 


116  KEY  AND   FLORA 

above  the  growing  bunches   of  spines.      Ovary  covered  with 
sepals.     Seeds  with  endosperm. 

m.    CE'REUS,  Column  Cactus 

Oval  or  columnar  plants,  sometimes  tall,  ribbed,  or  angled, 
with  bundles  of  spines  on  the  ribs.  Flowers  larger  than  the 
two  preceding,  close  above  the  bundles  of  full-grown  spines. 
Ovary  covered  with  sepals.  Seeds  without  endosperm. 

IV.    OPUN'TIA,  Jointed  Cactus 

Branching  or  jointed  plants,  with  joints  either  flattened  or 
cylindrical.  Spines  barbed,  and  accompanied  by  numerous 
short  bristles  that  easily  become  detached.  Ovary  bearing 
bristles  in  the  axils  of  small  terete  deciduous  sepals.  Seeds 
with  the  embryo  coiled  around  the  endosperm. 


FICOI'DEJE.     FIG  MARIGOLD  FAMILY 

Fleshy,  succulent  plants,  with  opposite  leaves  without  stip- 
ules. Petals  and  stamens  numerous,  inserted  on  the  tube  of 
the  calyx,  which  is  adnate  to  the  capsule. 

MESEMBRYAN'THEMUM,  Fig  Marigold,  Ice  Plant 

Calyx  lobes  5,  unequal.  Petals  numerous,  linear.  Stamens 
indefinitely  numerous.  Capsule  with  as  many  cells  as  styles 
(4-20),  usually  5,  dehiscent  at  the  top. 

M.  sequilatera'le  Haworth.  FIG  MARIGOLD.  Perennial,  with 
stout,  usually  prostrate  stems.  Leaves  thick,  3-sided,  smooth,  1-3 
in.  long.  Flowers  crimson,  nearly  sessile.  Fruit  edible.  This  is 
common  on  the  coast. 

ARALIA'CE-Ei.     GINSENG  FAMILY 

Perennial  herbs  or  shrubs,  generally  with  woody  stems. 
Umbels  not  regularly  compound.  Styles  and  carpels  more 
than  2.  Fruit  fleshy,  forming  a  berry  or  drupe. 


DICOTYLEDONOUS   PLANTS  117 


I.    ARABIA,  Ginseng,  Spikenard 

Calyx  5-toothed  or  entire.  Petals  5,  ovate.  Stamens  5. 
Pistil  with  the  ovary  2-5-celled,  and  the  styles  free  or  slightly 
united  at  base.  Leaves  alternate,  compound.  Umbels  simple, 
either  in  racemes  or  panicles.  Pedicels  not  jointed. 

A.  Califor'nica  Watson.  Herbs,  8-10  ft.  high,  from  a  thick  aro- 
matic root.  Leaves  large,  bipinnate,  with  ovate-lanceolate  leaflets, 
simply  or  doubly  serrate.  Umbels  globular,  generally  in  panicles. 
Fruit  when  ripe  forming  a  purple  berry.  This  is  frequent  along 
shaded  streams. 

H.    FAT'SIA,  Devil's  Club 

Densely  prickly  shrubs  with  large  palmately  lobed  leaves 
and  greenish  white  flowers  in  dense  paniculate  umbels. 
Calyx  teeth  wanting.  Petals  5,  valvate  in  bud.  Stamens  5, 
alternate  with  the  petals.  Ovary  2-3-celled  ;  styles  2.  Fruit 
a  drupe.  Pedicels  jointed. 

F.  hor'rida  Benth.  &  Hook.  Stems  stout,  woody,  creeping  at  base, 
leafy  at  summit,  very  prickly.  Leaves  roundish,  heart-shaped  in  out- 
line, prickly  on  both  sides.  Styles  united  to  the  middle.  This  is 
common  in  shady  woods  from  Oregon  northwards.  It  forms  thickets 
which,  on  account  of  the  thorny  stems,  are  almost  impassable. 


UMBELLIF'ERJE.     PARSLEY  FAMILY 

Herbs  with  hollow,  grooved  stems  and  small  flowers  in 
umbels.  Calyx  usually  a  5-toothed  rim  around  the  top  of 
the  ovary.  Petals  5,  small.  Stamens  5,  inserted  on  a  disk 
on  the  top  of  the  ovary.  Ovary  2-celled  and  2-ovuled,  ripen- 
ing into  2  carpel-like  akenes,  which  readily  separate  from 
each  other.  Each  carpel  bears  longitudinal  ribs,  in  the  fur- 
rows of  which  secondary  ribs  often  occur.  On  a  cross-section 
of  the  fruit  the  oil  tubes  are  seen  as  dots.  They  traverse  the 
spaces  between  the  ribs,  and  are  pretty  near  the  surface  of 
the  fruit.  The  seeds  contain  a  small  embryo  enclosed  in 
considerable  endosperm.  The  family  is  difficult,  and  the 


118  KEY   AND   FLOE A 

flowers  are  so  much  alike  that  the  different  genera  and 
species  are  to  be  distinguished  from  each  other  chiefly  by 
the  characteristics  of  the  fruit. 

I.    SANIC'ULA,  Snakeroot,  Sanicle 

Leaves  palmately  lobed  or  pinnately  divided.  Umbels 
simple  or  imperfectly  compound,  with  flowers  sessile  or  on 
short  pedicels.  Bracts  of  the  involucre  leafy,  toothed  ;  those 
of  the  involucels  small,  entire.  Fruit  covered  with  hooked 
prickles  or  tubercles.  Seeds  round,  with  oil  tubes  more  or  less 
obscure. 

a.  S.  arctopoi'des  H.  &  A.    YELLOW  MATS,  FOOTSTEPS  OF  SPRING. 
Stems  prostrate,  branching  from  the  base.     Leaves  deeply  3-lobed, 
with  the  divisions  raggedly  cleft.     Fruit  on  short  pedicels.     This 
is   very   conspicuous  in  early  spring,  dotting  the   ground  with  its  small 
mat  of  yellowish  green  Jlowers  and  leaves,  during  the  rainy  season.     It 
is  generally  in  bloom  early  in  January.     Throughout  California. 

b.  S.  bipinnatif'ida  Dougl.      PURPLE   SANICLE,  NIGGER-BABIES. 
Erect,    with    lower    leaves    opposite,     upper    alternate,    pinnately 
3-5-parted,    with   the   divisions   toothed    or    lobed    (generally   the 
teeth  are  tipped  with  bristles).     Flowers  purplish,  in  umbels  with  3 
or  4  elongated  rays.     Throughout  California. 

c.  S.  tubero'sa  Torr.    Stems  low  from  a  small  tuberous  root.    Leaves 
finely  dissected.     Involucre  with  1-4  rays,  leafy;  involucels  small, 
unequally   lobed.      Heads    small.      Flowers    yellow.     Fruit    covered 
with  tubercles  instead  of  prickles.     Widely  distributed,  often  growing 
on  stony  hills.     There  is  a  disagreeable  odor  about  the  plant. 

II.    HERACLE'UM,  Cow  Parsnip 

This  is  a  stout,  tall  herb  with  large  thrice-compound  leaves. 
Leaflets  broad,  deeply  and  irregularly  toothed.  Umbels  large, 
compound,  with  many-leaved  involucels.  Calyx  teeth  small 
or  none.  Petals  white,  conspicuous,  the  outer  ones  2-cleft  and 
larger  than  the  inner.  Fruit  tipped  with  a  thick  conical 
enlargement  of  the  style,  with  3  blunt  ribs  on  the  outside  of 
each  carpel,  and  a  large  oil  tube  in  each  interval  between  the 
ribs.  Seeds  flat. 

H.  lana'tum  Michx.  This  is  the  only  species.  The  stem  is  gen- 
erally woolly.  It  grows  everywhere  not  far  from  water. 


DICOTYLEDONOUS   PLANTS  119 


IE.    DAITCUS,  Carrot,  Rattlesnake  Weed 

Calyx  5-toothed,  fruit  oblong,  with  the  primary  ribs  bristly, 
and  the  secondary  ones  winged  with  a  row  of  barbed  prickles 
more  or  less  united.  Oil  tubes  under  the  wings.  Leaves 
much  dissected  with  very  small  segments.  Involucres  like 
the  leaves,  but  smaller.  Outer  rays  of  the  umbel  longest  and 
foiling  over*  the  others  in  fruit.  Flowers  greenish. 

D.  pusil'lus  Michx.    YERBA  DE  LA  VIBOKA,  RATTLESNAKE  WEED. 

Annual,  erect,  simple  or  branched,  with  the  umbels  terminating  the 
steins.  The  fruit  tastes  something  like  lemon  peel.  This  is  the 
most  widely  accepted  antidote  for  the  bite  of  the  rattlesnake. 
Widely  distributed. 


CORNA'CE^.     DOGWOOD  FAMILY 

Generally  trees  or  shrubs,  with  opposite  simple  and  entire 
leaves  without  stipules.  Flowers  in  heads  or  cymes.  Sepals, 
petals,  and  stamens  4.  Calyx  adnate  to  the  1  or  2  celled 
ovary,  which  becomes  a  1  or  2  seeded  drupe  or  berry  in  fruit. 
The  seeds  have  hard  endosperm  and  a  minute  embryo. 

COR'NUS,  Dogwood 
Calyx  minutely  4-toothed.     Petals  white  or  yellowish  green. 

<i.  C.  Nuttal'lii  Audubon.  LARGE-FLOWERED  DOGWOOD.  This 
is  usually  a  small  tree  with  smooth  bark.  Flowers  numerous  in  a 
head  surrounded  by  a  conspicuous  involucre  of  large  while  or  yell  on- is  It 
bracts  often  tinged  with  red  and  resembling  petals.  Berries  bright  red 
in  clusters.  This  grows  along  streams,  chiefly  in  the  northern  part 
of  California. 

b.  C.  pubes'cens  var.  Califor'nica  C.  &  R.  COMMON  DOGWOOD. 
Shrubby,  with  smooth,  reddish  branches.  Leaves  ovate  to  oval, 
acute  at  base,  acute  or  pointed  at  top.  Flowers  white  in  cymes, 
flowering  almost  throughout  the  year.  Fruit  dull  white,  rounded, 
with  stone  somewhat  flattened,  ridged  on  the  sides  and  furrowed  on 
the  edge.  This  is  common  throughout  the  state,  growing  along 
streams. 

c.  C.  stolonif'era  Michx.  Shrub  3-9  ft.  high,  bearing  stolons. 
Stems  bright  red-purple  and  smooth.  Leaves  lanceolate  to  oblong, 


120  KEY  AND   FLORA 

pointed  at  top,  obtuse  at  base,  white  on  the  lower  surface  from  the 
close  pubescence.  Flowers  in  small  cymes.  Calyx  teeth  minute, 
petals  white,  fruit  white  or  lead-color.  Oregon  to  British  Columbia. 

GARRYA'CE-flE.      SILK-TASSEL  BUSH  FAMILY 
GAR'RYA,  Silk-tassel  Bush,  Quinine  Bush 

Evergreen  shrubs  with  opposite  leathery  leaves.  Flowers 
grayish  green,  apetalous,  dioecious,  in  pendent  axillary  cat- 
kins, which  are  solitary  or  several.  Sterile  flowers  with 
4-parted  calyx,  and  4  conspicuous  stamens  on  distinct  fila- 
ments. Fertile  flowers  with  a  2-lobed  calyx  or  none,  styles  2, 
ovary  1-celled,  containing  2  ovules.  Fruit  a  berry  with  a 
brittle  outer  covering,  pulpy  within,  and  containing  1  or  2 
seeds.  This  is  the  only  genus. 

a.  G.  Fremon'tii   Ton.      Leaves  becoming   glabrous,  not  wavy- 
margined.     Fruit  very  bitter,  purple.     Sterile  catkins  2-3  in.  long. 
Middle  California. 

b.  G.  ellip'tica  Dougl.     Leaves  white-woolly  on  the  lower  surface, 
wavy-margined.     Fruit,  when  ripe,  red-purple,  pleasantly  acid,  with 
a  hint  of  bitterness.     The  sterile  catkins  are  from  2  to  5  in.  long, 
and   look   like    fringe.      From   Monterey  County   to    Oregon    and 
Washington. 

ERICA'CEJE.     HEATHER  FAMILY 

Herbs  or  woody  plants.  Leaves  simple,  evergreen  or 
deciduous,  without  stipules.  Stamens  as  many  or  twice  as 
many  as  the  parts  of  the  corolla ;  anthers  2-celled,  opening 
by  little  holes  at  the  top.  Ovary  generally  with  as  many 
cells  as  there  are  parts  to  the  corolla,  inferior  in  Vaccinium 
but  superior  in  the  other  genera.  Style  simple.  Fruit  a 
berry  or  a  pod  with  axillary  placentae. 

I.    VACCINIUM,  Huckleberry 

Shrubby.  Calyx  and  corolla  apparently  on  the  summit  of 
the  ovary,  the  calyx  tube  being  adnate  to  the  ovary.  Stamens 


DICOTYLEDONOUS  PLANTS  121 

8-10,  with  separate  cells  to  the  anthers,  which  taper  upwards. 
Fruit  a  berry  crowned  with  the  5-toothed  calyx. 

a.  V.  ova'tum  Pursh.     Leaves  -evergreen,  glossy,  serrate,  acute. 
Flowers  crowded  in  short  clusters  in  the  axils  of  the  leaves  and  at 
the  ends  of  the  branches.     Corolla  bell-shaped,  pink.     Stamens  10. 
Berries  dark  blue  or  purple,  edible.     This  is  common  in   the  Coast 
Mountains  from  Monterey  County  to  Oregon. 

b.  V.    parvifo'lium    Smith.       Stems   much   branched,    with   the 
branches   sharply   angled.     Leaves  deciduous,   oblong,  entire,    dull 
green  above,  pale  beneath.     Corolla  globular.    Stamens  10.    Anthers 
with  long  tail-like  appendages  on  the  back.     Berries  pale  red,  edible. 
Northern  California  to  Alaska. 


H.    AR'BUTUS,  Madrono,  Madrone 

Trees  with  thick,  evergreen,  alternate  leaves.  Flowers 
white,  in  terminal  panicles.  Calyx  small,  5-lobed.  Corolla 
urn-shaped,  with  5  recurved  teeth,  and  large  honey-glands 
near  the  base.  Stamens  10  ;  anthers  flattened,  with  a  pair  of 
horns  on  the  back  below  the  summit.  Ovary  raised  on  a  disk, 
5-celled.  Fruit,  when  ripe,  a  round  red  berry  with  a  rough, 
tubercled  surface,  edible  but  rather  dry. 

A.  Menzie'sii  Pursh.  This  is  a  beautiful  tree  or  sometimes  a 
shrub,  with  smooth,  browrnish  red  bark,  which  peels  off  in  the  sum- 
mer. The  leaves  are  large,  oblong,  serrate,  bright  green  above,  pale 
beneath.  The  tree  is  beautiful  at  all  times;  when  in  bloom  fra- 
grant and  adorned  with  large  panicles  of  flowers  like  lilies  of  the 
valley ;  in  autumn  gorgeous  with  the  large  clusters  of  fruit,  varying 
in  color  from  greenish  yellow  to  bright  scarlet,  as  large  as  green 
peas.  In  the  Coast  Mountains  and  Sierra  foothills  to  Puget  Sound. 


IH.    ARCTOSTAPH'YLOS,  Kinnikinick,  Manzanita 

Shrubs  with  alternate,  evergreen  leaves  and  smooth  bark 
that  peels  off  in  summer.  Flowers  white  or  pink,  variously 
clustered.  Calyx  small,  5-lobed.  Corolla  urn-shaped,  with 
5  recurved  teeth  and  large  honey-glands  near  the  base. 
Stamens  10,  anthers  flattened,  ivith  a  pair  of  horns  on  the  back 
at  the  summit.  Ovary  raised  on  a  disk,  5-celled.  Fruit  a 
berry,  containing  stony  seeds  that  are  separable  or  cohere 
into  one. 


122  KEY  AND   FLORA 

a.  A.  Manzani'ta  Parry.    COMMON  MANZANIT  A.    Erect  and  branch- 
ing, becoming  tree-like,  with  smooth,  polished  dark-red  stems  and 
branches.     The  young  shoots  and  the  leaves  are  ashy  gray,  becoming 
smooth  with  age.     The  leaves  are  generally  vertical  by  a  twist  in 
the  petiole.     Flowers  crowded  in  short  racemes  on  smooth  pedicels 
with    short,  pointed   bracts.      Fruit   smooth,   about  the   size   of    a 
pea.     This    sometimes   becomes  a  tree.     In    valleys   of   the    Coast 
Mountains. 

b.  A.  Stanfordia'na  Parry.     A  delicately  branched  shrub,  either 
erect  or  spreading,  with  slender  peduncles  and  pedicels,  small  scale- 
like  bracts  and  dark-green,  smooth  leaves,  round  and  small.      The 
flowers  are  smaller  than  in  other  species,  and  are  deep  rose-color,  rarely 
white.     The  berries  are  smooth,  rather  small,  and  the  seeds  coalesce 
more  or  less.     This  is  common  in  the  northern  Coast  Mountains, 
and  is  perhaps  the  most  beautiful  species. 

c.  A.  tomento'sa  Dougl.     Shrub  with  hairy  stems  and  leaves  more 
or  less  clothed  with  a  close  pubescence.     Flowers  in  short  panicles 
with   leafy   bracts  which  are  most    conspicuous  in  the   buds.     Flowers 
white,  rather  large.     Berries  with  the  seeds  coalescing  more  or  less. 
This  is  one  of  the  most  widely  distributed  species,  and  embraces  a 
great  many  forms  chiefly  distinguished  by  the  amount  of  pubes- 
cence.    It   is    never  destroyed   by  brush  fires,  and    the    old    roots 
become  chunks  of  solid  wood. 

d.  A.  canes'cens    Eastwood.     This    is    somewhat  similar  to    the 
preceding,  but  the  entire  plant  is  white-downy.     The  flowers  are  more 
often  pink  than  white,'  and  the  habit  of  the  plant  is  more  spreading. 
The  bracts  are  large  and  leaf-like.     This  is  widely  distributed  in 
northern  California. 

e.  A.  Anderso'nii  Gray.     This  is  similar  to  A.  tomento'sa.     The 
leaves  are  thin,  bright  green,  smooth  or  slightly  pubescent,  with 
the  base  arrow-shaped  or  heart-shaped,  either  sessile  or  short-petiole  d. 
It  is  found  in  the  Coast  Mountains  of  California,  in  San  Mateo, 
Santa  Cruz,  and  Alameda  Counties. 

/.  A.  vis'cida  Parry.  Shrub  3-5  ft.  high,  with  smooth,  pale-gray 
or  glaucous  leaves.  Panicles  erect  in  bud,  becoming  pendent  later. 
Flowers  pink  or  white,  rather  small,  on  slender,  very  viscid  pedicels. 
Fruit  a  berry  containing  seeds  that  coalesce  more  or  less.  The 
bracts  are  small  and  scale-like.  This  species  is  very  abundant  in 
the  foothills  of  the  Sierra  Nevada  and  in  the  hills  of  Lake  and 
Mendocino  Counties. 

g.  A.  glau'ca  Lindl.  BIG-BERRIED  MANZANITA.  The  foliage 
of  this  is  always  glaucous  and  smooth.  It  is  distinguished  from 
all  other  species  by  the  large  berries,  often  |  in.  in  diameter,  with 
the  stones  consolidated  into  a  thick,  solid  mass.  Most  common  south- 
ward. 


DICOTYLEDONOUS  PLANTS 

A.  A.  bi'color  Gray.  Shrub  3  or  4  ft.  high.  Leaves  oblong  to 
oval,  1-2  in.  long,  leathery,  clothed  with  white  down  on  the  lower 
surface,  green  and  glabrous  on  the  upper.  Corolla  rose-color,  small. 
Fruit  a  smooth  berry  with  a  solid  seed.  Southern  California,  espe- 
cially in  San  Diego  County. 

i.  A.  U'va-Ur'si.  KINNIKINICK.  Stems  forming  a  mat  on  the 
ground.  Leaves  small,  very  glossy.  Flowers  in  short,  simple 
racemes.  Fruit  bright  red  and  smooth  when  ripe.  Northern  Cali- 
fornia to  British  Columbia. 

There  are  many  other  species  more  local  and  difficult  to 
distinguish. 

IV.    GAULTHE'RIA,  Salal 

Stems  shrubby  but  slender,  ascending  or  spreading,  creep- 
ing under  ground.  Leaves  alternate,  broad,  evergreen, 
glossy.  Flowers  nodding,  solitary  or  in  racemes,  in  the 
axils  of  the  leaves.  Calyx  5-cleft,  becoming  fleshy  in  fruit 
and  enclosing  the  capsule.  Corolla  5-toothed.  Stamens  10 
within  the  corolla,  the  anthers  tipped  with  bristles.  Ovary 
5-celled,  with  many  ovules,  in  fruit  forming  a  sweet  aromatic 
berry  which  is  edible. 

G.  Shal'lon  Pursh.  SALAL.  Stems  sometimes  3-4  ft.  high, 
almost  climbing  among  trees  and  bushes.  Racemes  glandular. 
Corolla  pink,  urn-shaped.  Fruit  black  when  ripe,  with  dark-purple 
pulp.  From  Santa  Barbara  to  British  Columbia. 


V.    RHODODEN'DRON,  Azalea 

Calyx  very  small.  Corolla  large,  funnel-form,  5-lobed. 
Stamens  5-10,  with  long,  slender  filaments  reclining  along  the 
lower  side  of  the  flower.  Capsule  woody,  dehiscent  from  the 
summit,  at  the  partitions,  by  5  valves.  Flowers  showy,  in 
umbels,  the  bracts  falling  as  the  flower  opens. 

a.  R.  Califor'nicum  Hook.  ROSE  BAY.  Shrub  with  smooth  ever- 
green leaves.  Flowers  rose-color,  numerous,  in  a  terminal  umbel. 
Upper  lobes  of  the  corolla  yellowish  and  spotted  within.  This 
is  a  beautiful  shrub  of  northern  California,  Oregon  and  Wash- 
ington, often  growing  in  patches  covering  acres.  It  is  the  State 
Flower  of  Washington. 


124  KEY  AND  FLORA 

b.  R.  occidental  Gray.  AZALEA.  Shrub  with  bright-green  decid- 
uous leaves.  Flowers  large,  fragrant,  appearing  after  the  leaves,  in 
numerous  umbels.  Corolla  viscid,  white  or  rose-color,  the  upper 
lobes  blotched  with  yellow  within.  Stamens  and  styles  very  long. 
This  is  found  along  streams  in  both  the  Coast  and  Sierra  Nevada 
Mountains. 

VI.    LE'DUM,  Labrador  Tea 

Shrub  with  alternate,  evergreen  leaves  more  or  less  covered 
with  resinous  dots.  Flowers  white,  in  corymbs  or  umbels. 
Calyx  5-lobed,  small.  Corolla  of  5  obovate,  widely  spread- 
ing petals.  Stamens  5-10,  as  long  as  the  petals.  Pod 
5-celled,  with  5  valves  opening  from  the  base  upwards. 

a.  L.  glandulo'sum  Nutt.      Leaves  smooth  on  both  sides,   but  paler 
and  more  glandular  beneath.     Flower  clusters  often  crowded,  terminal 
or  axillary.    This  is  common  at  high  elevations  in  the  Sierra  Nevada 
and  on  the  coast  from  northern  California  to  British  Columbia. 

b.  L.  latifo'lium  Ait.     Leaves  densely  white-woolly  beneath,  becoming 
brownish,  margins  with  the  edges  turned  back,  oblong,  obtuse,  1-2  in. 
long,  £   in.   wide.     Flower   clusters   all   terminal.     Northern    Cali- 
fornia to  British  Columbia. 


VII.     CHIMAPH'ILA,  Prince's  Pine 

Herbs  with  low  stems  from  slender  rootstocks.  Leaves 
evergreen,  alternate  or  sometimes  opposite,  toothed.  Flowers 
few,  fragrant,  waxy-looking,  in  terminal  corymbs.  Petals  5, 
widely  spreading,  regular,  orbicular,  concave.  Stamens  10, 
on  short  filaments  which  are  dilated  and  hairy  in  the  middle. 
Stigma  round-shield-shaped,  concealing  the  short  style,  5-rayed. 
Pod  splitting  from  the  top  downwards,  not  woolly  on  the  edges 
of  the  valves. 

a.  C.  umbella'ta  Nutt.  Stems  about  6  in.  to  a  foot  high,  with 
the  leaves  often  in  whorls,  not  spotted.  Peduncle  4-7-flowered, 
with  the  bracts  narrow  and  deciduous ;  filaments  hairy  on  the  margins 
only.  California  to  British  Columbia. 

b.  C.  Menzie'sii  Spreng.  Stems  about  6  in.  high,  with  a  few 
branches  from  the  base.  Leaves  sometimes  mottled  with  white. 
Peduncles  1-3-flowered.  Filaments  slender,  with  a  woolly  dilated  cen- 
tral part.  California  to  British  Columbia. 


DICOTYLEDONOUS  PLANTS  125 


VIII.    PYR'OLA,  Wintergreen 

Herbs  with  radical  leaves  and  flowers  nodding  in  racemes, 
on  scapes.  Calyx  5-lobed.  Corolla  with  5  incurved  petals. 
Stamens  10,  usually  declined.  Anthers  erect  in  bud,  2-horned 
at  base,  but  becoming  inverted  when  the  flowers  expand.  Style 
declined  or  straight.  Fruit  a  capsule  opening  down  the 
middle  of  the  cell  walls  on  the  back. 

a.  P.  rotundifo'lia  L.    Leaves  round,  shining  or  dull,  on  long  peti- 
oles.    Scapes  from  6  in.  to  a  foot  high.     Flowers  white,  pink  or 
rose-color,    almost   £  in.  in   diameter.     Anthers   narrowed   at  top. 
Style  declined,  with  a  collar  at  base  of  the  stigma.     In  wet  places 
in  the  mountains,  widely  distributed. 

b.  P.  pic'ta  Smith.     Leaves  orbicular,  thick,  veined  or  blotched  with 
tvhite,  often  purplish  beneath.     Scapes  about  6  in.  high,  7-15-flowered. 
Petals  greenish  white,  longer  than  the  sepals.     Northern  California 
to  Alaska. 

c.  P.  aphyl'la  Smith.     Leafless  or  with  a  few  small,  poorly  formed 
leaves.     Scapes  reddish,  6  in.  high.     Flowers  similar  to  the  above, 
rose-color.     In  deep  woods  from  California  to  Washington. 


PRIMULA'CEJE.     PRIMROSE  FAMILY 

Herbs  with  perfect,  regular  flowers,  parts  of  the  calyx  and 
corolla  5  (sometimes  4,  6,  or  8).  Stamens  equaling  the  lobes 
of  the  corolla  and  opposite  them,  inserted  on  the  tube  of  the 
corolla.  Pistil  with  a  single  style  and  stigrna,  the  ovary 
1-celled,  with  a  globular  central  placenta. 

\       I.    DODECATHEON,  Twelve  Gods,  Shooting  Stars,  Prairie  Pointers, 

Cyclamen 

Herbs  with  leaves  clustered  at  the  base  of  the  scape. 
Flowers  showy,  in  simple,  terminal  umbels.  Calyx  5-cleft, 
with  the  divisions  reflexed  in  flower,  erect  in  fruit.  Corolla 
with  an  extremely  short  tube,  an  open  throat,  and  5  reflexed 
narrow  divisions,  which  are  white,  rose-color  or  purple.  Sta- 
mens inserted  on  the  throat  of  the  corolla,  with  short  monadel- 
phous  filaments,  and  long  yellow  or  violet  anthers  conniving 
around  the  long  style  and  forming  the  point  of  the  flower. 


126  KEY  AND  FLORA 

a.  D.  Henderso'ni  Gray.  Roots  becoming  small  tubers  and  each 
forming  a  new  plant.  Leaves  ovate  or  obovate,  smooth,  on  broad 
petioles.  Scape  6-12  in.  high.  Divisions  of  corolla  4  or  5,  rose- 
purple*;  tube  darker,  with  a  ring  of  yellow.  Anthers  erect.  Pod 
twice  as  long  as  the  calyx,  opening  by  a  lid  below  the  summit. 
This  is  the  commonest  species  in  early  spring  on  hillsides  of  the 
Coast  Mountains,  and  extends  from  middle  California  to  Oregon. 

b.  D.  Clevelan'di  Greene.  Roots  somewhat  fleshy,  but  not  forming 
tubers.  Stems  and  leaves  pale  green  and  glandular.  Leaves  ascend- 
ing, spatulate  or  obovate.  Divisions  of  corolla  bright  purple,  yellow 
at  base ;  tube  dark  purple  with  yellow  lines.  Pods  opening  by  a 
lid  at  top.  Southern  California. 

There  are  several  other  species,  chiefly  growing  in  the 
higher  mountains. 

II.    TRIENTA'LIS,  Star-flower 

Low  perennial  herbs  from  tuber-bearing,  slender  rootstocks. 
Stems  simple,  with  the  leaves  in  a  whorl  below  the  flowers. 
Flowers  small,  star-shaped,  on  slender  pedicels.  Calyx  and 
corolla  7-parted  (sometimes  6-9-parted),  with  divisions  widely 
spreading.  Stamens  with  slender  filaments  united  into  a  ring 
at  the  base.  Capsule  splitting  into  five  parts,  with  few  seeds. 

T.  Europse'a  var.  latifo'lia  Torr.  This  grows  in  the  woods  and 
blooms  in  the  spring.  The  petals  are  white  or  rose-color. 


III.    STEIRONE'MA 

Stems  erect,  leafy.  Leaves  entire,  opposite  or  whorled. 
Flowers  yellow,  axillary,  nodding  on  slender  pedicels.  Corolla 
wheel-shaped,  apparently  with  petals  distinct,  each  division 
wrapped  around  its  stamen  in  the  bud.  Filaments  united 
around  the  base  of  the  corolla  in  a  ring,  evert/  alternate  one 
being  sterile.  Capsule  many-seeded. 

S.  cilia'tum  Raf.  Stem  simple.  Leaves  ovate-lanceolate,  2-4  in. 
long,  rounded  or  somewhat  heart-shaped  at  base,  with  long  ciliate 
petioles.  In  moist  thickets.  Washington.  Summer. 

IV.    ANAGAL'LIS,  Pim'pernel,  Poor  Man's  Barometer 

Spreading  or  prostrate  annuals,  with  stem  leaves  opposite 
or  whorled.  Flowers  on  axillary  peduncles,  salmon-color,  with 


DICOTYLEDONOUS  PLANTS  127 

a  darker  spot  in  the  center  (rarely  blue  or  white) ;  calyx  and 
corolla  wheel-shaped.  Filaments  bearded.  Capsule  globose, 
the  top  falling  off  as  a  lid. 

A.  arven'sis  L.     This  is  common  everywhere,  and  has  been  intro- 
duced from  Europe. 


PLUMB  AGIN  A'CE^E,  SEA  PINK  FAMILY 

Ours  are  maritime  herbs,'  with  all  parts  of  the  flower  5, 
except  the  1-celled,  1-ovuled  ovary.  Leaves  alternate,  entire, 
clasping  the  stem.  Calyx  tubular  or  funnel-form,  5-toothed. 
Corolla  with  5  petals,  united  at  base  into  a  ring.  Stamens 
5,  opposite  the  petals,  and  inserted  at  their  base.  Ovary 
5-angled  at  summit,  with  1  ovule  ;  styles  5. 

I.    ARME'RIA,  Thrift 

Stemless  perennials,  with  narrow,  linear,  persistent  leaves 
in  close  tufts.  Flowers  in  a  head  subtended  by  an  involucre, 
on  a  long  scape.  Corolla  5-parted,  of  5  distinct  petals. 

A.  vulga'ris  Willd.  SEA  PINK.  Corolla  rose-color.  This  is  com- 
mon along  the  coast,  blooming  in  spring. 

H.    STAT'ICE,  Sea  Lavender 

Flowers  in  small  one-sided  spikes  crowded  at  the  ends  of  the 
numerous  widely  spreading  branches.  Leaves  with  a  broad, 
tough  blade  tapering  to  a  petiole. 

S.  Limo'nium  L.  var.  Califor'nica  Watson.  SEA  LAVENDER. 
Corolla  violet.  This  is  common  in  salt  marshes,  blooming  in 
summer. 

OLEA'CEJE.     ASH  FAMILY 

Trees  or  shrubs  having  opposite  leaves  without  stipules. 
Corolla  2  or  4  lobed.  Stamens  2.  Ovary  2-celled,  with  2 
ovules  hanging  from  the  top  of  each  cell.  Fruit  often  1-celled 


128  KEY   AND   FLORA 

and  1-seeded,  either  a  stone  fruit,  as  the  olive  ;  a  pod,  as  the 
lilac  ;  or  a  winged  fruit,  as  the  ash. 

FRAX'INUS,  Ash 

Trees  or  shrubs  with  compound  leaves  and  dioecious  or 
polygamous  flowers.  Calyx  small,  4-cleft.  Petals  2  or  none. 
Stamens  2,  with  large  anthers.  Fruit  winged  from  the  top. 

a.  F.  dipet'ala  Hook.  &  Arn.     FLOWERING  ASH.     A  small  tree 
or  shrub  with  5-7  separate  leaflets  on  petioles.     Flowers  showy,  in 
panicles.     Calyx  4-toothed.     Petals  2,  white,  as  long  as  the  anthers. 
This  grows  along  streams  in  the  Coast  Mountains. 

b.  F.  Orega'na   Nutt.     OREGON  ASH.     A  large  tree  with  dark- 
colored  bark.     Leaflets  5-7,  entire,  sessile,  usually  tomentose  when 
young,  becoming  smooth  with  age.     Flowers  without  petals.     From 
Fresno  County,  in  the  mountains,  to  Oregon  and  Washington. 

GENTIANA'CE^E.     GENTIAN  FAMILY 

Glabrous  herbs  with  entire  opposite  leaves  without  stipules. 
Stamens  as  many  as  the  lobes  of  the  corolla,  inserted  on  its 
tube,  and  alternating  with  the  lobes.  Stigmas  2,  sessile  or 
on  one  style.  Ovary  1-celled.  Fruit  with  2  parietal  placentae 
dehiscent  at  the  partitions.  Seeds  with  abundant  endosperm 
around  the  minute  embryo. 

ERYTHR^'A,   Canchalagua 

Low,  much-branched  herbs,  with  numerous  showy  flowers 
in  cymes.  Corolla  rose-color,  salver-form,  with  lobes  con- 
volute in  the  bud.  Anthers  twisting  spirally  after  the  pollen 
is  shed.  Stigmas  at  first  united,  wedge-shaped  or  fan-shaped, 
afterwards  spreading. 

E.  venus'ta  Gray.  Corolla  deep  pink,  with  yellow  center;  divi- 
sions half  as  long  as  the  tube.  This  is  the  handsomest  and  most 
widely  distributed  species. 

(True  gentians  are  rare  in  California,  and  are  mostly  con- 
fined to  the  high  mountains.) 


DICOTYLEDONOUS  PLANTS  129 


ASCLEPIADA'CE-32.     MILKWEED  FAMILY 

Herbs  with,  a  milky  juice  and  a  tough  inner  bark  having  a 
fiber  like  flax.  Leaves  opposite,  entire.  Flowers  peculiar  in 
shape,  in  umbels.  Sepals  and  petals  each  5,  reflexed.  Anthers 
forming  a  crown  united  to  the  solid  stigma,  and  with  peculiar 
hood-like  appendages  surrounding  it.  The  anther  cells  are 
orange  in  color,  and  are  concealed  in  the  crown,  and  have 
the  outline  of  a  pair  of  scales.  Fruit  a  pod,  opening  at  one 
side.  Seeds  arranged  symmetrically  on  a  thick  axis,  each 
provided  with  a  tuft  of  silky  down. 

I.    ASCLE'PIAS,  Silkweed,  Milkweed 

The  five  hoods  of  the  stamens  are  each  provided  with  a 
protruding  horn. 

a.  A.  specio'sa  Torr.     Covered  with  white  down.     Stems  stout, 
erect,  with  large,  thick,  oblong  leaves,  opposite  or  whorled.     Umbels 
on  peduncles  shorter  than  the  leaves,  many-flowered.    Flowers  large, 
purple ;  the  hoods  nearly  half  an  inch  long,  spreading,  with  a  horn- 
like prolongation  from  the  summit ;  besides  the  short,  inflexed  true  horn. 
Follicles  rough  with  soft  spinous  processes.     California  to  Washington. 
This  is  inclined  to  become  a  troublesome  weed. 

b.  A.  Mexica'na  Cav.     Stems  rather  slender,  3-6  ft.  high.    Leaves 
in   whorls  of   3-6,  linear,    sessile,   smooth,  3-6   in.  long.     Umbels 
clustered  to  form  a  corymb,  densely  flowered  on  peduncles  longer 
than  the  petioles.     Flowers  rather  small,  greenish  white  or  tinged 
witli  purple.     Hoods  broadly  ovate,  shorter  than  the  beak-like,  incurved 
horn.     Follicles  slender,  tapering  to  the  top.     California  to  Oregon, 
spreading  as  if  introduced,  along  highways. 

H.    GOMPHOCAR'PUS 

The  five  hoods  are  without  horns. 

G.  cordifo'lius  Benth.  Smooth,  with  ascending  stems,  2-3  ft.  high. 
Leaves  ovate,  clasping  by  a  heart-shaped  base,  opposite  or  some- 
times in  threes.  Umbels  1-4,  with  the  flowers  loose,  on  thread-like 
pedicels.  Corolla  dark  red-purple.  Horns  tipped  with  a  point 
where  the  open  edges  come  together.  Follicles  smooth,  inclined 


130  KEY   AND   FLORA 

to  be  erect,  on  deflexed  pedicels.  This  is  common  in  California, 
blooming  in  late  summer,  and  growing  in  dry  ground  in  the  valleys 
and  foothills. 

APOCYNA'CE^E.     DOGBANE  FAMILY 

Perennial  herbs  with  milky  juice  and  opposite  entire  leaves 
without  stipules.  Flowers  in  cymes  or  corymbs,  regular,  all 
the  parts  5,  except  the  pistil,  which  consists  of  2  ovaries,  with 
the  styles  and  stigmas  united.  Fruit  a  pair  of  slender  folli- 
cles. Seeds  with  a  tuft  of  silky  down. 

APOC'YNUM,  Indian  Hemp,  Dogbane 

Corolla  bell-shaped,  5-cleft,  with  5  scales  opposite  the  lobes 
and  near  their  base.  Stamens  inserted  on  the  base  of  the 
corolla,  with  short  filaments  and  arrow-shaped  anthers, 
uniting  into  a  ring. 

a.  A.  androssemifo'lium  L.     Corolla  rose-color,  with  revolute  lobes 
and  a  bell-shaped  tube  longer  than  the  calyx.     This  is  generally 
much    branched,    and    the   flowers    are    numerous    in    loose    cymes. 
Widely  distributed. 

b.  A.  cannab'inum  L.      Corolla  white,  with  erect  lobes,   and  the 
tube  not  longer  than  the  calyx.     Flowers  small,  in  dense  cymes. 
This  grows  in  marshy  places.     Widely  distributed. 

POLEMONIA'CEJE.     PHLOX  FAMILY 

Herbs  or  rarely  shrubs.  Leaves  simple  or  divided,  with- 
out stipules.  All  parts  of  the  flower  5,  except  the  pistil, 
which  has  a  3-lobed  style  and  a  3-celled  ovary  with  axillary 
placenta.  Stamens  on  the  tube  of  the  corolla,  alternate  with 
its  lobes.  Embryo  with  endosperm. 

GII/IA 

Herbs  or  rarely  shrubs.  Leaves  various,  alternate  or  oppo- 
site. Calyx  partly  herbaceous,  generally  papery  below  the 
folds,  with  lobes  narrow  and  acute.  Corolla  from  funnel-form 


DICOTYLEDONOUS  PLANTS  131 

and  salver-shaped  to  bell-shaped  and  wheel-shaped.  The 
seeds  generally  become  mucilaginous  when  wet.  The  flowers 
are  showy,  and  among  our  most  characteristic  spring  annuals  ; 
the  species  are  numerous,  and  are  not  always  easily  distin- 
guished. Only  the  most  distinct  and  common  are  given. 

a.  G.    grandiflo'ra    Dougl.      SALMON-COLOR    GILIA    (Collo'mia). 

Flowers  crowded  at  the  summit  of  an  erect  stem ;  corolla  pale 
salmon-color,  with  the  tube  nearly  an  inch  long  and  the  border 
almost  as  broad.  Widely  distributed. 

b.  G.   squarro'sa  Esch.     SKUNKWEED   (Navarre'tia) .     Stems  low, 
branching   diffusely,  viscid.     Leaves  and  bracts  pinnately  parted, 
with  spiny  divisions.     Flowers  small,  deep  blue.     This  blooms  late 
in  the  summer.      The  whole  plant  has  the  odor  of  the  skunk.     Widely 
distributed. 

c.  G.  tricolor  Benth.     BIRD'S  EYES.     Stems  slender,  branching. 
Corolla  %  in.  long,   with  a  yellow  tube,  the  funnel-form  throat  marked 
with  deep  violet-purple,  and  the  limb  white  or  lilac.     It  is  sweet-scented 
and  very  pretty.     Throughout  western  California. 

d.  G.   dicho'toma  Benth.     EVENING   SNOW    (Linan'thus).     Erect 
and  branching  herbs  with  very  slender  stems.     The  leaves  are  few, 
small,  and  far  apart.     Flowers  large,  terminating  the  peduncles,  salver- 
form,  with  the  divisions  convolute  in  the  bud,  showing  only  the  dull-pink 
outer  edges,  opening  about  4  o'clock.     Where  they  are  abundant  they 
look  like  snow  on  the  ground.     The  white  flowers  are  often  more 
than   an   inch   in    diameter,    and    have   a   sweet,    heavy   perfume. 
Throughout  western  California. 

e.  G.    androsa'ceus     Benth.     (Linan'thus).      Stems     leafy,    with 
palmately  parted  leaves,  apparently  whorled,  with  thread-like  divi- 
sions.     Flowers    crowded    in    a   terminal   cluster.       Corolla   salver- 
form,  with  a  long,  slender  tube,  rose-color,  lilac  or  white.     This  is  a 
handsome  and  widely  distributed  species,  but  variable  and  difficult 
to  distinguish  from  allied  species. 

/.  G.  micran'tha  Steud.  Smaller  in  all  its  parts  than  the  pre- 
ceding, with  the  tube  of  the  corolla  long  and  thread-like,  l-l£  in. 
long.  Flowers  small,  rose-color,  white,  or  lilac.  Common  through 
California. 

g.  G.  cilia'ta  Benth.  Stems  slender,  erect,  clothed  with  white 
hairs.  Flowers  and  bracts  in  a  dense,  capitate  cluster,  very  hispid 
and  ciliate.  Corolla  small,  pink  or  white,  extending  beyond  the 
bracts  but  little.  This  is  widely  distributed  through  California, 
and  common.  . 

h.  G.  dianthoi'des  Endl.  FRINGED  GILIA.  Stems  from  an  inch 
to  less  than  a  foot  high,  simple  or  branching  from  the  base.  Leaves 
thread-like.  Corolla  pink,  with  yellowish  throat  and  very  short  tube. 


132  KEY   AND   FLORA 

The  corolla  lobes  are  fringe-toothed.  This  is  common  in  southern 
California,  and  is  one  of  the  prettiest  spring  annuals. 

t.  G.  Califor'nica  Benth.  Shrubby,  2  or  3  ft.  high,  with  rigid 
branches.  Leaves  with  spiny  divisions,  widely  spreading,  clustered. 
Corolla  rose-color,  fading  to  lilac,  salver-form,  with  the  border  an 
inch  or  more  in  diameter,  the  lobes  often  shortly  fringed  on  the 
margin.  This  is  common  in  southern  California,  chiefly  on  dry 
hills.  It  is  very  showy,  with  its  numerous  flowers,  like  those  of 
phlox,  in  dense  clusters  terminating  the  branches. 

j.  G.  aggrega'ta  Spreng.  SCARLET  GILIA,  WILD  CYPRESS. 
Steins  erect,  simple  or  branched,  viscid.  Leaves  compound,  with 
narrow,  linear  leaflets.  Flowers  in  a  close  panicle.  Corolla  salver- 
form,  nearly  1  in.  long,  scarlet,  pink  or  white,  extremely  variable  in 
color.  This  grows  in  the  mountains  or  near  streams  on  the  plains. 
Summer. 

CONVOLVULA'CE^.     MORNING-GLORY  FAMILY 

Twining  or  trailing  herbs,  with,  alternate  leaves,  and  flowers 
solitary  or  few,  on  peduncles  in  the  axils  of  the  leaves.  Calyx 
of  distinct  sepals.  Stamens  alternating  with  the  parts  of  the 
corolla.  Ovary  2  or  3  celled,  with  a  pair  of  ovules  in  each 
cell.  Capsule  globular,  containing  1-4  seeds. 


I.    CONVOL'VULUS,  Morning-glory 

Corolla  open  funnel-form,  with  the  border  5-angled.  Sta- 
mens inserted  within  the  tube.  Style  slender.  Stigmas  2. 
Capsule  2-celled  and  generally  4-seeded,  with  dehiscent  septi- 
fragal  dehiscence  (the  valves  separate  from  the  partition). 
Cotyledons  folded  and  crumpled  in  the  seed  with  some 
endosperm. 

a.  C.  Soldanel'la  L.     SEASIDE  MORNING-GLORY.     Low  and  trail- 
ing herbs,  with  stem  and  leaves  fleshy.     Leaves  kidney-shaped,  on  long 
petioles.     Bracts  of  the  peduncle  close  to  the  calyx,  thin  in  texture. 
Corolla  pink  or  purple,  an  inch  or  more  in  length.     Pod  becoming 
1-celled.     This  grows  on  sandy  beaches. 

b.  C.    villo'sus    Gray.      Stems  trailing.      Leaves   hastate.     Bracts 
narrow,  close  under  the  calyx.      Corolla  cream-color,  an  inch  long. 
The    entire  plant   is    covered   with    a   close,   soft,   velvety,  while   down. 
Throughout  California,  but  not  very  common. 


DICOTYLEDONOUS   PLANTS  133 

c.  C.  lute'olus  Gray.  Stems  often  twining  over  high  bushes, 
smooth,  blooming  at  all  seasons.  Peduncles  as  long  as  the  leaves, 
with  a  pair  of  linear  or  lanceolate  bracts  a  little  below  the  flower  (no 
bracts  directly  under  the  calyx).  Corolla  pale  cream-color,  or 
(when  growing  near  the  coast)  light  or  deep  rose-color.  Through- 
out California. 

II.    CUS'CUTA,  Dodder,  Love  Vine 

Parasitic  plants  with  yellow  or  orange  stems,  scales  in  place  of 
leaves, and  densely  clustered  small  white  flowers.  Calyx  5-clef t 
or  parted.  Corolla  bell-shaped  or  tubular.  Stamens  inserted 
on  the  throat  of  the  corolla,  with  fringed  scales  below.  Ovary 
2-celled,  containing  4  ovules.  Styles  2,  distinct.  Embryo  with- 
out cotyledons,  thread-like,  spirally -coiled  in  hard  endosperm. 
The  seeds  germinate  in  the  soil,  but  do  not  form  roots  there. 
Instead,  they  attach  themselves  to  the  other  plants  by  means  of 
little  roots,  and  take  all  their  nourishment  from  their  hosts. 

a.  C.  sali'na  Engelm.     SALT-MARSH  DODDER.     Corolla  having  a 
shallow   bell-shaped    tube.       Capsule   pointed.       This    grows    in    salt 
marshes  on  plants  belonging  to  the   Chenopodiacece. 

b.  C.  subinclu'sa  Durand  &  Hilgard.      Corolla  with  a  rather  long, 
urn-shaved  tube.     Capsule  conical.     This  grows  on  shrubs  or  coarse 
herbs. 

HYDROPHYLLA'CE^.     BABY-EYES  FAMILY 

Herbs,  or  rarely  shrubs,  with  alternate  leaves  without  stip- 
ules (rarely  opposite).  Flowers  in  coiled  spikes  or  racemes, 
usually  showy.  Calyx  5-parted,  or  of  5  separate  sepals. 
Corolla  5-lobed.  Stamens  on  the  corolla  tube,  and  alternate 
with  its  lobes  and  shorter.  Styles  2  or  2-cleft.  Capsule  1  or 
2  celled,  with  2  parietal  placentae,  splitting  along  the  back  of 
each  valve. 

I.    HYDROPHYL'LUM,  Waterleaf 

Herbs  from  fleshy,  running  rootstocks.  Leaves  large,  alter- 
nate, pinnately  compound.  Flowers  white  or  blue,  in  close  or 
open  cymes,  on  long  peduncles.  Corolla  bell-shaped,  with  a 
honey-gland  at  the  base  of  each  lobe.  Stamens  and  style 
longer  than  the  corolla.  Filaments  bearded  at  the  middle. 
Styles  2-cleft.  Ovary  1-celled. 


134  KEY   AND   FLORA 

a.  H.  occidenta'le    Gray.     Stems   perennial,    1-2  ft.  high,    hairy. 
Leaves  broad,  pinnately  divided  ;    divisions  7-15,  oblong,    1-2  in. 
long,  the  apex  cut  into  long,  uneven  teeth,  obtuse.     Cymes  on  long 
peduncles,  densely  flowered.     Calyx  with  erect,  narrow,  lanceolate, 
obtuse    divisions.       Corolla    pale    violet   or    white.       California    to 
Washington. 

b.  H.  capita'tum  Dougl.      BEAR'S  CABBAGE.      Low,  from  many 
fleshy   roots.       Leaves    pinnately    5-7-parted  or  divided,   with    the 
divisions  2-3-lobed  or  cleft  into  oblong,  mucronate  lobes,  soft-hairy, 
broadly  ovate  in  outline,  2-3  in.  long.     Flowers  densely  clustered 
in  close  cymes  like  heads,  on  peduncles  shorter  than  the  petioles. 
Calyx  clothed  with  stiff  hairs.     Corolla  dull  white  or  violet.    From 
California,  in  the  mountains  at  rather  high  elevations,  to  Washing- 
ton.    It  comes  up  and  blooms  very  soon  after  the  snow  melts. 


II.    NEMO'PHILA 

Annual  herbs,  flowering  very  early,  with  the  leaves  pin- 
nately lobed  or  divided,  the  lowest  leaves  opposite.  Flowers 
solitary,  on  long  peduncles  in  the  axils  of  the  leaves.  Calyx 
5-parted,  with  a  reflexed  lobe  at  each  sinus,  enlarging  and 
covering  the  fruit.  Corolla  generally  saucer-shaped,  the  throat 
within  having  10  scales.  Style  2-cleft.  Capsule  1-celled. 

a.  N.  auri'ta  Lindl.     CLIMBING  NEMOPHILA.     Stems  succulent, 
long  and  weak,  clinging  for  support  to  other  plants  by  means  of 
stiff  reflexed  bristles.     Leaves  deeply  cut  into  5-9  lobes,  curved  down- 
tvards,   dilated   at   base,  and  auriculate.      Corolla  violet,   the    throat 
purplish.     Southward  from  San  Francisco. 

b.  N.  macula'ta    Benth.     Low    annuals,   growing   in    the    higher 
Sierras.      Corolla  white,  with  a  violet  spot  on  each  lobe. 

c.  N.  insig'nis  Dougl.     BABY-BLUE-EYES.     Low,  spreading,  grow- 
ing in  sandy  places.      Corolla  clear  blue,  nearly  an  'inch  in  diameter. 
This  is  the  commonest  species. 

d.  N.  atoma'ria  Fisch.  &  Meyer.     Low,  spreading,  growing  in  wet 
places.      Corolla  white,  dotted  with  dark  purple. 

e.  N.   intermedia   Bioletti.     Taller  than  the  last   two,    growing 
amid  the  brush.     Corolla  light  blue,  with  lines  and  dots -radiating  to 
the  center. 

III.    ELLIS'IA 

Leaves  once  or  twice  divided.  Flowers  small  and  white. 
Calyx  without  the  reflexed  lobes.  Corolla  generally  shorter, 


DICOTYLEDONOUS   PLANTS  135 

or  but  little  longer  than  the  calyx,  which  enlarges  under  the 
fruit.     Style  2-cleft.     Capsule  1-celled. 

a.  E.  membrana'cea  Benth.  Stems  succulent,  light-green,  smooth 
except  for  some  stiff  bristly  hairs  that  sometimes  help  support  the  //v  <tk 
stems.  Leaves  pinnately  divided  into  3-9  obtuse,  linear  divisions 
with  margined  petioles.  This  generally  grows  in  shady  and  damp 
places.  From  middle  California  to  San  Diego. 

1.  E.  chrysanthemifolia  Benth.  Stems  much  branched.  Leaves 
2  or  3  times  divided  into  small  and  short  divisions.  Flowers  in  loose 
racemes  on  short,  slender  pedicels.  From  middle  California  to  San 
Diego. 

IV.    PHACE'LIA 

Herbs  with  simple  or  compound  leaves,  and  flowers  in 
loosely  or  closely  coiled  spikes  or  racemes.  Calyx  deeply 
5-jHtrted,  without  reflexed  lobes.  Corolla  readily  falling, 
blue,  white,  or  purple  (rarely  rose-color),  from  wheel- 
shaped  to  funnel-form,  with  vertical  scales  attached  between 
the  bases  of  the  filaments,  sometimes  attached  to  the  fila- 
ments. Pistil  with  2-cleft  style  and  2-celled  ovary.  Seeds  4 
to  many. 

a.  P.  circina'ta  Jacq.  Perennial  from  a  stout  root,  a  foot  or 
two  high.  Leaves  grayish  green,  hairy,  simple,  or  the  lowest  compound 
iritli  1  or  2  pairs  of  leaflets.  Spikes  crowded,  conspicuously  coiled. 
Corolla  small,  whitish  or  lilac.  Stamens  conspicuous.  This  is 
found  in  many  forms  and  is  widely  distributed. 

1).  P.  divarica'ta  Gray.  Annual,  low,  with  spreading  branches 
inclined  to  be  prostrate.  Leaves  oblong  on  petioles  shorter  than  the 
blades,  simple  or  with  1  or  2  teeth  or  lobes  at  the  base.  Flowers  in 
loose  racemes,  corolla  bluish  purple,  f  in.  in  diameter. 

c.  P.  Menzie'sii  Torr.  Stems  6-10  in.  high,  branching  above, 
gray  with  a  close  pubescence  and  rough  with  stiff  hairs.  Leaves 
linear,  entire  or  cleft  into  linear  lobes.  Flowers  in  spikes  or  spike- 
like  racemes  which  are  clustered  to  form  close  panicles.  Corolla 
violet  or  white,  half  inch  or  more  in  diameter,  with  long,  narrow 
appendages  at  base,  free  from  the  filaments.  Pod  shorter  than  the 
calyx,  with  several  seeds.  From  California,  in  the  Sierra  Nevada 
to  British  Columbia. 

The  species  are  numerous,  and  many  are  local ;  nearly  all 
are  beautiful,  with  conspicuous  flowers. 


136  KEY   AND   FLORA 


V.    EMMENAN'THE,  Whispering  Bells 

This  chiefly  differs  from  Phacelia  in  the  corolla,  which  is 
bell-shaped,  withering-persistent,  and  becoming  papery,  yellow 
or  yellowish  white,  sometimes  tinged  with  pink. 

E.  penduliflo'ra  Benth.  Annual,  simple  up  to  the  inflorescence 
or  branched  diffusely  from  the  hase,  from  a  few  inches  to  a  foot  high. 
The  leaves  are  divided  into  numerous  short,  toothed  or  sharply  cut 
lobes.  The  racemes  are  panicled,  with  the  bell-shaped  flowers  on 
slender  pedicels  that  are  at  first  erect,  but  afterwards  droop.  This 
grows  in  dry  places  from  Lake  County  to  San  Diego. 


VI.    ERIODIC'TYON,  Yerba  Santa 

Low-branching  erect  shrubs.  Leaves  alternate,  dentate, 
petioled,  with  the  chief  nerves  pinnate,  and  the  others  form- 
ing a  network.  Flowers  in  cymes,  coiled  at  the  tips,  and 
generally  collected  in  terminal  clusters.  Corolla  funnel-form, 
violet,  purple,  or  white,  without  internal  scales.  Stamens 
with  filaments  adnate  to  the  tube  of  the  corolla.  Styles  2, 
distinct  at  the  base.  Capsule  pointed,  2-celled,  splitting  on  the 
back  and  at  the  sides  into  4  hard,  thick  half-valves. 

a.  E.  tomento'sum  Benth.     The  entire  plant  is  white  or  rusty, 
with  a  dense  coat  of  short  woolly  down.     Southern  California. 

b.  E.  grutino'sum  Benth.     This  is  rather  smooth  and  viscid,  with 
a  balsamic  exudation.     Throughout  the  Coast  Mountains. 


VII.    HESPEROCHI'RON 

Dwarf,  stemless  perennials  with  entire,  spatulate,  or  oblong 
leaves.  Flowers  on  .naked,  slender  peduncles,  shorter  than 
the  leaves,  from  the  leaf  axils.  Calyx  and  corolla  with  the 
parts  5-7,  the  former  with  linear-lanceolate  lobes  which  are 
sometimes  unequal,  the  latter  rotate  or  campanulate,  white 
or  purplish,  with  hairy  base.  Stamens  inserted  at  the  base 
of  the  corolla  with  hairy  filaments.  Ovary  cone-shaped,  some- 
what adnate  to  the  calyx,  tapering  to  the  rather  stout  style  which 
is  2-cleft  at  apex,  with  small  stigmas.  Ovary  1-celled.  Seeds 
many. 


DICOTYLEDONOUS   PLANTS  137 

a.  H.  Californicus  Watson.     Leaves  many  in  a  cluster  at  base. 
Corolla  oblong-campanulate,  tvith  the  lobes   longer  than  the  tube,  about 
half  an  inch  long.     From  California  in  the  Sierra  Nevada  to  Wash- 
ington ;  blooming  as  soon  as  the  snow  melts. 

b.  H.  pu'milus  Porter.     Leaves   fewer.      Corolla  nearly  rotate,   its 
lobes  longer  than  the  tube  which  is  densely  bearded  within,  about  half  an 
inch  across.     Same  range  and  time  of  blooming  as  the  preceding. 

BORRAGINA'CEJE,  BORAGE  FAMILY 

Herbs  usually  with  stems  and  leaves,  rough-hairy.  Leaves 
alternate,  entire,  without  stipules.  Flowers  in  panicles, 
cymes,  or  ra^mes,  coiled  at  the  tips,  usually  on  one  side  of 
the  peduncles.  Calyx  5-parted  or  cleft.  Corolla  salver-form. 
Stamens  inserted  on  the  tube  of  the  corolla,  alternating  with 
its  lobes.  Ovules  4,  solitary,  at  the  base  of  the  simple  style, 
usually  all  ripening  into  4  nutlets.  The  coiled  flower  clusters 
become  straight  as  the  flowers  open. 

I.    HELIOTRO'PIUM,  Heliotrope 

Calyx  5-parted.  Corolla  funnel-form.  Stamens  with  short 
filaments  or  none,  and  anthers  sometimes  cohering  by  their 
pointed  tips.  Style  simple  or  none,  with  an  umbrella-shaped 
stigma.  Seeds  with  endosperm. 

H.  Curassa'vicum  L.  Smooth,  glaucous,  succulent,  prostrate 
herbs,  growing  in  moist,  salty  or  alkaline  places.  Flowers  white  or 
pale  violet  in  dense  spikes,  which  are  generally  2-forked.  Widely 
distributed. 

II.     AMSINCK'IA,  Fiddle-neck,  Woolly  Breeches 

Hairy  annuals,  with  conspicuous  yellow  or  orange  flowers  in 
curved  spikes  or  racemes  without  bracts.  Many  are  covered  with 
bristly  hairs  that  have  a  pustulate  base.  Calyx  5-parted. 
Corolla  funnel-form,  with  the  tube  longer  than  the  calyx. 
Stamens  with  short  filaments  included  in  the  corolla.  Stigmas 
2-lobed,  capitate.  Nutlets  ovate-triangular,  attached  above 
the  base  to  a  narrow  pyramidal  column  called  the  gynobase. 
The  species  are  difficult  to  distinguish. 


138  KEY   AND   FLORA 


III.     CYNOGLOS'SUM,  Hound's  Tongue,  Forget-me-not 

Calyx  5-parted,  open  in  fruit.  Corolla  tubular  or  salver-form, 
with  conspicuous  crests  in  the  throat.  Nutlets  4)  covered  over 
the  lack  with  short,  stout  prickles  with  barbed  tips,  forming  burs. 
These  are  rather  coarse  perennials,  with  large  leaves  and 
thick  roots. 

C.  gran'de  Dougl.  ./Stems  a  foot  or  two  high,  branching  above. 
Leaves  mostly  at  the  base  on  long  petioles,  oblong-ovate.  Flowers  in 
panicled  racemes  on  a  long  naked  peduncle.  Corolla  similar  to 
the  fcrget-me-not,  but  larger,  at  first  pinkish,  with  white  crests  in 
the  throat,  turning  blue  after  pollination.  Monterey  County  to 
Washington. 

IV.    MERTEN'SIA,  Bluebells 

Stems  erect,  leafy,  not  hispid,  sometimes  smooth.  Leaves 
broad,  the  upper  ones  sessile,  the  lower  petioled.  Flowers 
nodding,  in  cymes  or  panicled  racemes.  Corolla  blue,  often 
turning  pink  after  pollination,  trumpet-shaped  or  bell-shaped, 
with  folds  in  the  throat.  Nutlets  sessile,  on  a  flat  or  slightly 
convex  receptacle. 

a.  M.  oblongifo'lia  Don.     Stems  about  a  foot  high,  almost  smooth. 
Leaves  oblong  or  somewhat  spatulate,  rather  succulent  and  with 
veins  scarcely  evident.     Corolla  blue,  with  tube  twice  as  long  as  the 
border,  together  about  half  an  inch  long.     Flowers  in  a  close,  terminal 
cluster.     Stamens  with  the  filaments  as  broad  as  the  anthers  and 
about  the  same  length,  inserted  in  the  throat  of  the  corolla.     Bloom- 
ing in  early  spring,  growing  on  moist  banks.     Oregon  to  British 
Columbia. 

b.  M.  panicula'ta  Don.     Stems  1-5  ft.  high,  more  or  less  rough 
with  pubescence.     Leaves  broad,  veiny,  ovate  to  oblong-lanceolate. 
Flowers  blue,  in  loosely  panicled  racemes.     Corolla  tube  but  little 
longer  than  the  border,  about  as  long  as  the  hairy,  linear,  calyx  divisions, 
together  a  half  inch  or  more  in   length.     From  Washington  to  the 
Arctic  regions. 

(Most  of  the  other  genera  are  in  a  state  of  confusion,  because 
of  the  differences  of  opinion  among  botanists.  The  differ- 
ences between  them  lie  chiefly  in  the  seeds,  and  they  are 
difficult  to  distinguish.) 


DICOTYLEDONOUS  PLANTS  139 


LABIA'T^E,  MINT  FAMILY 

Herbs  or  shrubs  with  4-angled  stems  and  opposite  leaves. 
Flowers  generally  in  whorls,  or  solitary  in  the  axils  of  the 
leaves.  Calyx  ribbed,  with  many  nerves.  Corolla  2-lipped. 
Stamens  4  in  two  sets,  2  often  sterile.  Fruit  of  4  nutlets 
around  a  simple  style.  These  plants  are  generally  aromatic. 

I.  MEN'THA,  Mint 

Calyx  5-toothed.  Corolla  with  short  tube,  naked  within, 
and  4-cleft  border,  scarcely  2-lipped,  but  with  the  upper  lobe 
broadest.  Stamens  If.,  nearly  equal,  erect,  distant.  Flowers 
small,  white  or  purplish,  in  whorls.  Aromatic  and  sweet- 
scented  herbs.  (There  are  several  cultivated  species.) 

a.  M.  Canaden'sis  L.     Flowers  all  in  axillary  whorls,  the  summit 
of  the  stem  being  flowerless.     Calyx  hairy.     Common  in  damp  places. 

b.  M.   Pule'gium   L.     Covered  with   a   white-woolly  pubescence. 
Calyx   slightly   2-lipped,    10-ribbed,    the   throat  closed  with  hairs. 
Recently  introduced,  but  spreading  rapidly. 

II.  MONARDEL'LA 

Calyx  tubular,  with  5  short,  nearly  equal  teeth,  and  the 
throat  naked  within.  Corolla  with  the  tube  longer  than  the 
calyx,  smooth  within  ;  upper  lip  2-cleft,  lower  one  3-parted, 
with  flat,  oblong-linear  lobes.  Stamens  4,  projecting  beyond 
the  corolla.  Flowers  in  terminal  heads  having  conspicuous 
involucres. 

a.  M.  villo'sa  Benth.     Perennial  herbs  with  many  stems  from  a 
woody  base,  soft-hairy.     Leaves  ovate,  strongly  veined.     Bracts  of  the 
involucre  similar  to  the  leaves.     Flowers  flesh-color,  white,  or  most 
frequently  purple.     Widely  distributed,  and  blooming  at  all  seasons. 

b.  M.  odoratis'sima   Benth.     Perennial  with  several  stems  from 
a  woody  root,   G-12  in.   high,  pale  green  or  gray  with  a  minute 
pubescence.     Leaves  oblong  to  lanceolate,  entire,  on  short  petioles,  with 
veins  inconspicuous.     Bracts  thin  and  membranous,  veiny,  white  or 
purple.     Calyx  teeth   hairy.     Common  in  the  mountains  of  Cali- 
fornia and  extending  to  Washington. 


140  KEY   AND    FLORA 

c.  M.  lanceola'ta  Gray.     Annual,  with  stems  loosely  branching,  a 
foot  or  more  high,   green   and   almost  smooth-     Leaves  oblong  or 
lanceolate,  tapering  into   a  slender  petiole.     Bracts  ovate  or  ovate- 
lanceolate,    with    cross    veinlets    between    the  principal    veins.      Corolla 
purple ;   calyx  teeth  acute,  densely  hirsute    within,  almost    smooth 
without.     Throughout  California  in  the  valleys  and  plains. 

d.  M.    can'dicans   Benth.     Annual,    gray,  with    soft    pubescence. 
Leaves  lanceolate  to  narrowly  oblong,  obtuse,  tapering  to  a  petiole. 
Bracts  ovate,  somewhat  papery,  white  with  greenish  nerves  ;  cross  veinlets 
betiveen  the  principal  nerves.       Corolla   white,  small  and  short;  calyx 
teeth  short,  obtuse,  tipped  with  white  wool  on  both  sides.     Through 
middle  and  southern  California. ' 


III.    MICROME'RIA,  Yerba  Buena 

Calyx  tubular,  equally  5-toothed.  Corolla  short,  naked 
within ;  upper  lip  erect,  entire  or  notched,  lower  spreading, 
3-parted.  Stamens  4-  These  are  sweet-scented  plants,  with 
small  lavender  flowers  in  the  axils  of  the  leaves. 

M.  Douglasli  Benth.  Perennial  herbs,  spreading  by  trailing 
stems.  Leaves  round-ovate,  sparingly  toothed.  This  usually  grows 
in  the  shade  of  bushes  and  trees  in  the  Coast  Mountains. 


IV.    SPHA'CELE 

Calyx  bell-shaped,  5-cleft,  thin,  membranous,  enlarged  in  fruit 
and  persistent.  Corolla  oblong,  bell-shaped,  with  5  broad  and 
roundish,  erect  lobes,  and  a  hairy  ring  at  the  base  of  the  tube 
within.  Stamens  Jf,  distant,  one  pair  shorter. 

S.  calyci'na  Benth.  Shrubby  at  base,  with  many  leafy  stems. 
Flowers  an  inch  long,  solitary  in  the  upper  axils,  forming  a  raceme. 
Corolla  white  or  tinged  with  purple.  The  entire  plant  has  a  sweet 
aromatic  perfume.  From  middle  California  southward. 


V.    SAI/VIA,  Sage 

Ours  are  all  herbs.  Calyx  2-lipped,  with  the  upper  lip  2  or 
3  toothed,  lower  2-cleft.  Corolla  deeply  2-lipped,  with  the 
upper  lip  erect,  entire,  notched,  or  rarely  2-lobed.  Stamens  2, 
with  filaments  apparently  forked,  one  end  bearing  a  linear 


DICOTYLEDONOUS   PLANTS  141 


anther  cell,  the  other  end  a  mere  rudiment  of  an  anther  cell. 
The  nutlets  when  wet  become  mucilaginous  and  send  out  spiral 
threads. 

a.  S.  cardua'cea  Benth.     THISTLE  SAGE.     Leaves,  clustered  at  the 
root,    white-woolly,    thistle-like.     Flowers    in    "whorls.      Corollas   large, 
bright  blue.     This  is  a  very  showy  plant  of  the  interior  valleys  of 
California. 

b.  S.  Columba'riae  Benth.     CHIA.     Leaves  wrinkled  with  numerous 
veins,    once  or  twice  parted   into   oblong,    crenate  or  toothed  divisions. 
Flowers  in  one  or  more  rather  distant  whorls  on  the  naked  stems. 
Corolla   rather   small,    dark   blue.     Involucre    of    entire    leaves,    like 
bracts.     Widely  distributed. 

VI.    AUDIBER'TIA,  California  Sage,  Bee  Sage 

Shrubby  plants  with  leaves  wrinkled  and  veiny,  finely 
crenate.  Flowers  similar  to  those  of  Salvia,  except  that  the 
filament  has  but  one  linear  anther  cell,  and  shows  the  remains 
of  the  connective  as  a  sort  of  spur.  The  various  kinds  of  sage, 
so  well  known  as  honey  plants,  all  belong  to  this  genus. 
They  are  most  abundant  in  southern  California,  where  they 
sometimes  clothe  the  hillsides. 


*  Flowers  in  dense  whorls  at  intervals  along  the  stem.     Bracts  crowded 
and  conspicuous.     Shrubs. 

a.  A.  niv'ea  Benth.     WHITE  SAGE.     Stems  and  leaves  covered 
with   a   snow-white   down.     Whorls    an   inch   across,   usually  2-4. 
Corolla  lavender  or  lilac,  with  the  tube  scarcely  longer  than  the  lips. 
Stamens  and  style  conspicuously  extending  beyond  the  corolla.     The 
bracts  and  the  calyx  teeth  are  blunt. 

b.  A.  stachyoi'des  Benth.     BLACK  SAGE.     Stems  and  leaves  ashy 
gray,  becoming  greener  and  smoother  with  age.     Clusters  of  flowers 
3-5  at  long  intervals,  on  slender  stems.     Corolla  lavender,  half  an 
inch  long.     Calyx  teeth  and  bracts  bristle-tipped. 

**  Flowers  in  a  close  panicle.     Floral  leaves  and  bracts  of  the  small  and 
numerous  clusters  lance-shaped  or  awl-shaped.     Shrubs. 

c.  A.  polystach'ya  Benth.     WHITE  SAGE,  GREASE  WOOD.    Stems 
many,  erect,  covered  with  a  fine  white  down  ;  inflorescence  a  foot  or 
so  in  length  ;  flowers  nearly  sessile.     Calyx  with  the  upper  lip  broad, 


142  KEY  AND  FLORA 

the  lower  with  3  long  teeth.  Corolla  half  an  inch  or  more  long, 
white  or  lavender,  with  a  short  tube  and  broad  lower  lip.  Stamens 
and  styles  long,  conspicuously  exserted.  This  is  said  to  be  the  best 
honey  sage. 

***  Flowers  large,  in  dense  whorls.      Woody  only  at  base. 

(I.  A.  grandiflo'ra  Benth.  Stem  stout,  2-3  ft.  high,  woolly  and 
glandular.  Leaves  wrinkled,  white  tomentose  on  the  lower  surface, 
sinuate-crenate.  The  lower  ones  are  broadly  lanceolate,  with  the 
base  somewhat  arrow-shaped,  3-8  in.  long  on  margined  petioles  ;  the 
upper  are  oblong  and  sessile.  Corolla  l£  in.  long,  bright  red,  with 
tube  longer  than  the  limb.  Bracts  broad  and  membranaceous. 
Stamens  extending  beyond  the  corolla.  This  is  common  from 
near  San  Francisco  southward.  It  generally  grows  in  the  hills. 

VII.    SCUTELLA'RIA,    Skullcap 

Low  perennial  herbs,  with  flowers  in  the  axils  of  the  leaves 
on  short  peduncles.  Calyx  helmet-shaped.  Corolla  with  an 
arched  upper  lip  and  dilated  throat.  Stamens  Jf.,  the  lower  pair 
ivith  1-celled  anthers,  the  upper  with  2-celled  bearded  anthers. 

a.  S.    tubero'sa  Benth.     Low  from  slender  underground  stems  ter- 
minating in  small  tubers.     Leaves  ovate,  toothed,  on  slender  petioles. 
Flowers  dark  blue,  over  half  an  inch  long.      From  Santa    Barbara 
County  northward. 

b.  S.    Calif  or'nica    Gray.      Stems  several,  from   slender   rootstocks. 
Leaves  entire,  narrowed  at  base.     Flowers  yellowish  white,  about  two- 
thirds  of  an  inch  long.     Northern  California  to  Oregon. 

c.  S.   angustifo'lia  Pursh.     Stems  erect,  leafy.     Leaves  oblong  to 
linear,  mostly  sessile,   entire,  except  for  a  few  teeth  on  the  lower  ones. 
Pedicels  as  long  as  the  calyx.     Corolla  nearly  an  inch  long  with 
slender  tube  and  dilated  throat ;  lower  lip  woolly  within.     Through- 
out California  to  British  Columbia. 

d.  S.    galericula'ta   L.      Stems   slender,   1-3    ft.  high,  simple  or 
branched  above.     Leaves  ovate-lanceolate,  almost  sessile,  serrate,  except 
at  the  top.      Corolla  dark  blue,   less  than   1   in.  long.      Widely  dis- 
tributed.    Summer. 

VIII.    BRUNEI/LA,  Self-heal 

Perennial  herbs  with  usually  simple  stems  and  sessile, 
3-flowered  flower-clusters  in  the  axils  of  kidney-shaped  bracts, 


DICOTYLEDONOUS   PLANTS  143 

the  whole  forming  a  spike  or  head.  Calyx  tubular,  bell-shaped, 
somewhat  10-ribbed,  upper  lip  broad,  3-toothed,  the  teeth 
short  ;  lower  lip  with  2  longer  teeth.  Upper  lip  of  the  corolla 
upright,  arched,  and  entire,  the  lower  spreading,  reflexed, 
fringed,  and  3-cleft.  Stamens  4)  reaching  up  under  the  upper 
lip,  with  the  tips  of  the  filaments  2-toothed,  only  one  tooth  anther- 
bearing. 

B.    vulga'ris    L.     SELF-HEAL,    HEAL-ALL,    CARPENTER    WEED. 

Leaves  with  petioles,  ovate-oblong,  either  entire  or  toothed,  often 
somewhat  hairy  ;  corolla  usually  dark-blue  or  purplish,  somewhat 
longer  than  the  brown-purple  calyx.  This  is  often  abundant  in 
damp  places,  and  is  widely  distributed. 

IX.    MARRU'BIUM,  Horehound 

Perennial  herbs  with  many  stems,  forming  a  clump  a  foot 
or  two  high,  white-woolly.  Calyx  with  usually  10  nerves  and 
teeth,  the  alternate  ones  spiny-tipped  and  recurved.  Corolla 
with  upper  lip  narrow,  arched  and  2-lobed  ;  lower  spreading 
and  3-cleft.  Stamens  4,  having  anthers  with  the  2  cells  not  dis- 
tinct. Flowers  in  dense  whorls,  in  the  axils  of  the  upper 
leaves.  This  is  a  widely  spread,  introduced  plant. 

M.  vulga're  L.  Leaves  roundish,  wrinkled,  crenate.  Corolla 
small  and  white.  The  bitter  aromatic  juice  is  used  as  a  remedy  for 
colds. 

X.    STA'CHYS,  Hedge  Nettle 

Perennial  herbs  with  a  disagreeable  odor,  —  some  species 
growing  near  water  becoming  very  tall.  Flowers  nearly  ses- 
sile, in  scattered  whorls,  purplish  or  white.  Calyx  5-toothed, 
5-10-nerved.  Corolla  with  tube  not  dilated  at  the  throat,  the 
upper  lip  erect,  arched,  entire  or  notched,  lower  spreading,  8-lobed, 
the  middle  lobe  longest.  Stamens  4)  with  2-celled  anthers. 

a.  S.  bulla'ta  Benth.     Stems  one  or  several,  loosely  branching, 
rough  with  downward-pointing  hairs.      Leaves  ovate,  cordate,  cre- 
nate, obtuse,  with  petioles  an  inch  or  two  long.     Flowers  red-purple, 
in  whorls,  forming  an  interrupted  spike.     This  grows  everywhere  in 
California,  and  blooms  almost  throughout  the  year. 

b.  S.  al'bens  Gray.     Stems  erect,  1-5  ft.  high,  clothed  through- 
out with  soft  white  wool.     Leaves  oblong,  cordate  at  base,  crenate, 


144  KEY  AND  FLORA 

2-3  in.  long;  upper  sessile;  lower  with  short  petioles.  Flowers  whit* 
on  a  wand-like  spike  in  dense  interrupted  close  clusters.  Calyx  with 
spine-tipped  teeth  nearly  equaling  the  tube  of  the  corolla.  California 
in  the  Sierra  Nevada  Mountains  and  hills  of  southern  California. 

c.  S.  Chamisso'nis  Benth.     Stems  erect,  2-6  ft.  high,  with  stiff 
hairs  pointing    downwards,    on    the    angles.      Leaves    oblong-ovate, 
3-5  in.  long,  crenate,  wrinkled  with  the  veins,  whitish,  with  woolly 
hairs  on  the  lower  surface,  stiff er  ones  on  the  upper.     Spike  6-12  in. 
long.       Calyx    with  spine-lipped    teeth,    densely   hairy.       Corolla  pur- 
plish,   |    in.    long,  hairy ;  lower   lip    half   as  long.     A  very  showy 
species  along  the  Californian  coast  from  San  Francisco  northward. 

d.  S.  cilia'ta  Dougl.     Similar  to  the  above,  but  with  the  -leaves 
greener  and  thinner ;  corolla  smaller,  with  the  tube  smooth.     Along 
the  coast  of  Oregon  and  Washington. 

XI.    TRICHOSTE'MA,  Blue-curls,  Camphor  Weed 

Shrubs  or  herbs  with  flowers  in  dense,  usually  one-sided 
axillary  cymes,  stamens  and  corolla  blue  or  purple  (rarely 
white).  Calyx  bell-shaped,  almost  equally  5-cleft.  Corolla 
with  a  slender  tube,  5-parted,  the  divisions  forming  in  bud 
a  roundish  ball  which  encloses  the  coiled  stamens.  Stamens 
spirally  coiled  in  the  bud,  conspicuously  protruding  from  the  open 
corolla.  In  bloom  in  summer  and  fall. 

a.  T.  lanceola'tum  Benth.     CAMPHOR  WEED.     Annual  herbs  with 
several  branches,  erect  from  the  base.     Leaves  crowded,  sessile,  lance- 
shaped.      Cymes    almost    sessile,    conspicuously   one-sided,    densely 
flowered.       Corolla    and   calyx    somewhat    hairy    or    woolly.       This 
plant  is  called  camphor  weed,  because  it  has  a  strong  odor  some- 
what like  camphor,  but  very  disagreeable,  sometimes  causing  head- 
ache.    Widely  distributed  in  the  interior  valleys. 

b.  T.  lax'um  Gray.     Annual,  diffusely  branched,  soft,  pubescent. 
Leaves  few,  lanceolate-oblong,  narrowed  to  an  obtuse  apex,  2-3  in.  long, 
on  slender  petioles.     Cymes  loosely  flowered,  on  peduncles.     Common 
from  middle  to  northern  California,  growing  in  dry  places. 

c.  T.    lana'tum   Benth.     ROMERO.     Shrubby,    3    or   4    ft.    high. 
Leaves    numerous,    narrowly   linear,    with    margins    turned    under, 
smooth    and    shiny    above,    white-woolly    on    the    under    surface. 
Flowers  in  numerous  cymes  in  a  close  terminal  cluster,  destitute  of 
bracts.      The  whole  inflorescence,  even  to  the  calyx  and  corolla,  is  covered 
ivith  dense  violet  wool.     The  filaments  extend  an  inch  or  more  beyond 
the  corolla.     Southern  California,  in  rocky  places.     It  is  very  con- 
spicuous and  beautiful. 


DICOTYLEDONOUS   PLANTS  145 


SOLANA'CE^E,  NIGHTSHADE  FAMILY 

Herbs  or  shrubs  with  leaves  alternate  and  without  stipules. 
Flowers  regular,  with  the  parts  in  fives,  except  the  single  style 
and  2-celled  ovary.  Fruit  a  many-seeded  berry  or  capsule. 
Seeds  with  curved  embryo  and  endosperm.  This  family  con- 
tains Tobacco,  Tomato,  Nightshade,  Egg-plant,  Potato,  and 
Chili-pepper. 

I.    SOLA'NUM,  Nightshade,  Potato 

Corolla  wheel-shaped,  5-parted  or  cleft.  Stamens  with  short 
filaments  and  distinct  anthers,  which  often  apparently  unite 
around  the  style.  Fruit  usually  a  berry. 

a.  S.  Douglas'ii  Dunal.     Somewhat  shrubby,  widely  branching  or 
even    climbing  by  the   rough    angles    of   the   branchlets.      Leaves 
ovate,   entire,  or  with  large  teeth,  1-2   in.  long.      Corolla  white  or 
bluish,  small.     Berries  black.     Common  throughout  California,  near 
the  coast. 

b.  S.  ni'grum  L.     COMMON  NIGHTSHADE.     Annual,  with  stems 
branching  diffusely.      Corolla  small,  white.      Berries  black  when  ripe, 
as  large  as  peas,  in  numerous  umbels  on  axillary  peduncles.     This  is 
common  everywhere  in  waste  ground. 

c.  S.    umbellif'erum   Esch.     Shrubby   at   base,    much   branched, 
with  leaves  and  stems  hoary.     Flowers  in  umbels,  the  corolla  bluish 
purple,    f    in.    in    diameter.     The    leaves    vary    extremely.      Widely 
distributed. 

d.  S.  Xan'ti  Gray.     Similar  to  the  above,  but  either  smooth  or 
glandular-hairy ;  leaves  thin.     Corolla  generally  larger.     This  is  more 
common  in  southern  California. 


H.    DATU'RA,  Thorn-apple 

Stout,  widely  branching  herbs  with  rank  odor  and  narcotic- 
poisonous  qualities.  Flowers  large,  on  short  stems  from  the 
axils  of  the  leaves.  Calyx  tubular,  5-toothed,  deciduous, 
leaving  a  circular  disk  under  the  fruit.  Corolla  broadlij 
funnel-form,  convolute  in  the  bud.  Pistils  with  long  style 
and  2-lipped  stigma.  Capsule  prickly  all  over.  Seeds  large, 
kidney-shaped. 


146  KEY  AND  FLORA 

D.  meteloi'des  DC.  Perennial,  spreading,  and  often  tall,  hoary 
Leaves  unequally  ovate,  wavy  on  the  margin,  or  entire.  Corolla 
white  or  pale  violet,  with  the  border  broadly  expanded,  the  5  angles 
terminating  in  long,  slender  awns.  Pods  large  on  recurved  peduncles. 
Southern  California. 

m.    NICOTIA'NA,  Tobacco 

Herbs  (one  a  tree)  with  rank  odor  and  narcotic  poisonous 
properties.  Calyx  bell-shaped,  5-toothed  or  lobed,  closely 
surrounding  the  capsule.  Corolla  salver-form  or  funnel-form, 
with  a  very  long  tube.  Stamens  with  slender  filaments  and 
broad  anthers  included  in  the  tube  of  the  corolla.  Pistil  with 
long,  slender  style  and  2-celled  ovary,  stigma  2-lobed  or  cap- 
like.  Capsule  splitting  generally  at  the  junction  of  the  valves 
and  on  the  back,  appearing  Celled. 

a.  N.  glau'ca  Graham.     TREE   TOBACCO.     This  has  been  intro- 
duced from  South  America,  and  is  now  widely  distributed  in  southern 
California.     It  is  a  shrub   or   small   tree   with   pale-green   foliage. 
Flowers   in   loose   terminal  panicles ;  corolla  2    in.  long,  greenish 
yellow,  with  a  long  tube,  narrowed  at  the  throat;  border   erect, 
5-crenate. 

b.  N.  attenua'ta  Torr.     Stems  simple  or  branching,  very  viscid. 
Leaves  oblong-lanceolate,  pointed  at  both  ends.     Flowers  in  loose, 
terminal   racemes.     Calyx   teeth   short,  triangular,  acute.     Corolla 
white,  narrow,  salver-form,  the  tube  an  inch  long  and  the  border  %  in. 
across.     Pod  exceeding  the  calyx.     This  is  widely  distributed  and  is 
frequently  found  along  highways. 

c.  N.  Bigelo'vii  Wats.     Similar  to  the  preceding  but  with  sessile 
leaves.     Calyx  with  unequal  lobes,  corolla  tubular,  funnel-form,  with 
tube  an  inch  or  more  long  and  the  border  an  inch  across ;  pod  shorter 
than  the  calyx.     This  is  also  found  along  highways. 


SCROPHULARIA'CEJE,  FIGWORT  FAMILY 

Herbs  and  shrubs  with  corolla  2-lipped  or  otherwise*  more 
or  less  irregular  (2  lobes  belong  to  the  upper  lip  of  the  corolla  ; 
3  to  the  lower).  Stamens  2  or  4  (2  long  and  2  short),  or  5, 
with  one  lacking  the  anther.  Pistil  with  a  simple  style  and 
2-celled  ovary.  Fruit  a  2-celled  pod,  with  the  seeds  on  an 
axillary  placenta,  splitting  from  the  top. 


DICOTYLEDONOUS  PLANTS  147 


I.    VERONICA,  Speedwell 

Low  herbs  with  opposite  leaves,  and  flowers  in  axillary 
racemes  cr  solitary.  Calyx  and  corolla  4-parted,  with  the  lobes 
more  or  less  unequal.  Stamens  2.  Pod  inversely  heart-shaped. 

a.  V.    Americana   Schweinitz.     Smooth   herbs   growing   in   wet 
places,  with  the  stems  rooting  at  the  joints.     Leaves  ovate  or  oblong, 
on  petioles.    Flowers  numerous,  small,  bright  blue  with  darker  stripes. 
Widely  distributed. 

b.  V.    peregri'na    L.      Annual,    3-10   in.    high,   erect,    with    few 
branches.     Lower   leaves   opposite,    upper  alternate,    linear-oblong, 
obtuse,  entire  or  toothed.     Flowers  on    short  pedicels    in  the  leaf 
axils.     Corolla  very  small,  white.     Capsule  many-seeded.     Common, 
apparently  an  introduced  weed. 

H.    SCROPHULA'RIA,  Figwort,  Bee-plant 

Perennial  herbs  with  opposite  leaves,  and  small  flowers  in 
loose  cymes  arranged  in  a  terminal  panicle.  Calyx  5-cleft, 
with  broad,  rounded  lobes.  Corolla  with  a  globular  tube  and 
5  lobes  ;  four  are  erect  and  the  fifth  turned  down  or  spreading. 
Stamens  4  in  &  pairs,  shorter  than  the  lobes  of  the  corolla  and 
inserted  low  on  the  tube.  A  rudiment  of  a  fifth  stamen 
appears  in  the  form  of  a  scale  on  the  upper  side  of  the 
throat  of  the  corolla. 

S.  Califor'nica  Cham.  CALIFORNIAN  BEE-PLANT.  Stems  2-5  ft. 
high,  nearly  smooth.  Leaves  oblong-ovate,  usually  cordate  at  base, 
coarsely  doubly  toothed  or  incised.  Flowers  brownish  purple,  less 
than  half  an  inch  long,  the  rudimentary  stamen  narrowly  wedge- 
shaped  or  spatulate.  The  honey-glands  produce  a  large  quantity 
of  honey  which  can  usually  be  seen  within  the  corolla  tube.  This 
is  widely  distributed  and  common. 

m.    COLLIN'SIA 

Low  annual  herbs  with  opposite  leaves,  and  flowers  some- 
what resembling  pea  blossoms.  Corolla  2-lipped,  with  the 
lower  li^W-lobed  and  the  middle  lobe  compressed  at  the  sides, 
including  th'e  style  and  stamens  ;  tube  short,  with  a  protuber- 
ance at  the  base  on  the  upper  side,  the  mouth  closed  by  an 


148  KEY   AND   FLORA 

inward  projection  of  the  lower  Up  like  a  palate.  Stamens  4 ; 
a  small  gland  at  the  base  of  the  corolla  on  the  upper  side 
answers  to  the  fifth  stamen. 

a.  C.    bi'color   Benth.     A  foot  or  so  high;  leaves  more  or  less 
toothed,  the  upper   ovate-lanceolate,  and  sessile  by  a   broad   base. 
Flowers   on    short  pedicels,    in   racemes    at   th&   summit    of  the   stem ; 
corolla    with    the    upper    lip    nearly    white,    the    lower    rose-color. 
Widely  distributed  in  California. 

b.  C.  Francisca'na  Bioletti.     Similar  to  the  last,  but  the  flowers 
are   on    longer    pedicels,   more   numerous  in   the  whorls ;    and    the 
throat  of  the  corolla  is  entirely  closed  by  the  palate.     This  grows  around 
San  Francisco  and  is  very  common. 

c.  C.  tincto'ria  Hartweg.     Flowers  almost  sessile.     Corolla  yellow- 
ish or  white,  marked  with  purple  dots  or  lines,  the  upper  FLp  and 
its  lobes  very  short.      The  plant  is  covered  with  a  yellowish  or  broivnish 
glandular  pubescence  that  stains  the  hands.     This  is  common  in  the 
foothills  of  the  Sierras. 

d.  C.    bartsiaefo'lia  Benth.     Leaves    thickish    in    texture,    linear   to 
ovate-oblong,    crenate.     Flowers    on    short   pedicels,  crowded    in   the 
axils  of  the  leaves  or  bracts.     Corolla  nearly  white,  with  the  throat 
bearded,  and  longer  than  broad,  upper  lip  about  the  length  of  the 
curved  throat.     This  grows  in  sandy  soil  in  the  central  and  western 
parts  of  California. 

e.  C.  parviflo'ra  Dougl.     Stems  slender,  branching,  2-6  in.  high, 
leaves  lanceolate  or  oblong,  narrowed  at  base  and  entire,  sometimes 
whorled.     Flowers  on  slender  pedicels,  solitary  or  several  in  a  whorl. 
Flowers  small,  less  than  |  in.  long.     Corolla  blue  and  white,  a  little 
longer  than  the  narrow,  triangular  calyx  lobes.     Common  in  the 
Sierra  Nevada  range   and  north  to  British  Columbia.     In  bloom 
early. 

IV.    PENTSTE'MON 

Perennial  herbs  with  opposite  leaves,  the  upper  sessile  or 
partly  clasping.  Calyx  5-parted.  Corolla  red,  purple,  blue, 
white  (rarely  yellow),  2-lipped,  with  a  more  or  less  inflated 
tube  ;  upper  lip  2-lobed,  lower  3-cleft  or  spreading.  Stamens 
4,  the  fifth  a  conspicuous  filament  without  an  anther.  Pod 
usually  pointed,  splitting  from  the  top  into  two  parts. 

a.  P.  cordifo'lius  Benth.  Stems  very  leafy,  climbing  over  bushes 
by  long  branches.  Leaves  cordate,  serrate,  or  toothed.  Flowers  in 
a  leafy  panicle.  Corolla  scarlet,  with  a  long  narrow  tube.  Sterile  fila- 
ment bearded.  Common  in  southern  California. 


DICOTYLEDONOUS   PLANTS  149 

b.  P.   heterophyl'lus   Lindl.      Stems  many  from    a   woody  base, 
pale-green.      Leaves  lance-shaped  or  linear.     Corolla  rose-purple,  an 
inch   long.     Anthers  shaped  like   a  horseshoe,   with   the    base  of  each 
cell    remaining    closed,    and   forming   a   sac,    dilate    on    the    opened 
edges.       Sterile    filament    smooth.       Throughout    California    in    dry 
places. 

c.  P.  centranthifo'lius  Benth.     Light  bluish  green  and  perfectly 
smooth.     Upper  leaves  heart-shaped,  clasping.     Corolla  fully  an  inch 
long,  bright  red,  tubular,  hardly  bilabiate,  with  the  lobes  spreading  but 
little.     Sterile  filament  slender  and  smooth.     Most  common  in  southern 
California. 

d.  P.   gla'ber   Pursh.      Stems    1-2  ft.    high,    smooth,    glaucous. 
Upper   leaves   ovate-lanceolate,  clasping  the  stem.      Flowers   in   a 
long,   close   panicle.     Sepals   ovate,    pointed.     Corolla   violet,  with 
swelling  throat,  1-1 1  in.  long.     Sterile  filament  with  a  few  hairs  at 
top.     Anthers  opening  from   the  base  of  each  cell  to   the  apex,  smooth 
or  slightly  hairy.     Along  streams.     Summer. 

e.  P.  confer'tus  var.  caeruleo-purpureus  Gray.    Stems  slender,  erect, 
smooth,  except  for  the  viscid  pubescence  about  the  flowers.     Leaves 
linear  to  lanceolate.     Flowers  rather  small,  in  2-5  whorls,  1  in.  or 
more  apart.     Sepals  with  papery,  fringed  margins  and  pointed  tips. 
Corolla   purplish   blue,    2-lipped,    the    lower    lip   bearded.     Anthers 
opening  from  base  to  apex,  the  two  valves  spreading  out  fat,  after  the 
pollen  has  been  discharged.     Sterile  filament  bearded.     In  the   moun- 
tains.    Summer. 

V.    CASTILLE'JA,  Indian  Paint-brush 

Perennial  herbs  generally  with  several  stems  from  woody 
roots.  Leaves  sessile.  Flowers  in  simple  spikes,  with  the 
bracts  large  and  colored  red,  white,  or  yellowish.  Calyx  colored 
like  the  bracts,  tubular,  more  or  less  cleft  either  in  front  or 
behind  or  on  both  sides.  Corolla  tubular,  with  a  long-pointed 
upper  lip,  lower  lip  very  small,  3-toothed,  with  3  folds  or 
small  sacs  below  the  short  teeth  (the  tube  is  usually  enclosed 
in  the  calyx).  Stamens  4>  enclosed  in  the  upper  lip.  Style 
long,  with  stigma  cap-shaped  or  2-lobed. 

a.  C.  affi'nis  Hook  &  Am.  Sterns  often  tall,  branched  from  the 
base.  Leaves  simple,  linear-lanceolate,  entire.  Flowers  somewhat 
distant  below  but  crowded  above,  curved.  Upper  leaves,  bracts,  and 
calyx  more  or  less  colored  red.  Corolla  yellowish  or  reduish,  an  inch 
or  tn ore  long,  curved,  surpassing  the  red  calyx,  the  lower  lip  very 
short.  Middle  to  southern  California. 


150  KEY   AND   FLORA 

b.  C.  foliolo'sa  Hook  &  Arn.     Stems  generally  in   a  bunch,   white- 
woolly.      Leaves    short    but  numerous,    lowest  entire,    upper    floral 
leaves  cleft,  with  the  tips  dilated,  yellowish  or  red.     This  is  common 
only  on  dry  hills  of  the  Coast  Mountains. 

c.  C.  latifo'lia  Hook  &  Arn.     Stems  leafy,  1  to  several  from  the 
root,  viscid-pubescent.     Leaves  short  and  broad,  the  upper  ones  3-5- 
lobed,  tinged   with    red.     Calyx  lobes  longer    than  the  tube   of  the 
corolla.     Near  the  coast,  from  Monterey  County  northward. 


VI.    ORTHOCAR'PUS,  Owl's  Clover 

Low  annual  herbs,  similar  to  Castilleia  in  having  spikes  of 
flowers  with  the  cleft  bracts  and  calyx  divisions  colored. 
Calyx  short,  tubular,  4-cleft.  Corolla  tubular,  with  the 
upper  lip  hardly  longer  than  the  lower,  small  in  comparison 
with  the  lower,  which  is  inflated  and  in  several  species  has  3 
round  sacs. 

*  Bracts  with  tips  colored  like  a  corolla. 

a.  0.    purpuras'cens   Benth.     ESCOBITA.     Simple   and    erect,    or 
branched  at  the  base,  hairy.      Spike  dense,  oblong,  the  lobed  bracts 
and  the  calyx  divisions  crimson.       Upper  lip  of  the  corolla  densely 
bearded  with  crimson   hairs,  hooked  at  the   apex,  the  lower  lip   with  3 
very  small  sacs.     Stigma  large,  globose,  densely  covered  with  purple 
hairs.     Very  common  in  spring.     Widely  distributed. 

b.  0.    densiflo'rus  Benth.      OWL'S-CLOVER.      This   is    similar   to 
the  above,  except  that  the  upper  lip  of  the  corolla  is  straight  and  the 
lobes  of  the  bracts  and  of  the  calyx  white  and  crimson ;  the  leaves  are 
soft,  pubescent,  with  few  lobes,  or  entire  at  the  base.     Along  the 
coast. 

**  Bracts  not  colored  like  a  corolla. 

c.  0.  erian'thus  Benth.     Slender,  with  many  branches  ;  stems  and 
bracts  dark  red.     Corolla  deep  yellow,  the  upper  lip  slender,  pointed, 
dark-purple,  the  sacs  on  the  lower  lip  large,  round,  and  deep,  the  tube 
very  slender.     Monterey  County  northward. 

d.  0.  versi'color  Greene.      POP-CORN  FLOWER.      Similar   to   the 
last,  but  the  flowers  are  pure  white,  fading  pinkish.      In  one  variety 
the  flowers  are  rose-color  from  the  first.     This  species  is  very  fra- 
grant.    Around  San  Francisco. 

e.  0.    lithospermoi'des    Benth.       Steins    rather    stout,    generally 
simple,  l-l£  ft.  high,  very  leafy.     Flowers  in  a  dense  spike.     Calyx 


DICOTYLEDONOUS  PLANTS  151 

lobes  linear.  Corolla  deep  yellow,  fading  whitish,  an  inch  or  more  long, 
with  3  large  sacs.  This  blooms  later  than  the  others.  Throughout 
California. 

There  are  many  species  besides  these. 


VII.    PEDICULA'RIS 

Perennials  with  one  to  several  stems  from  a  thick  root. 
Leaves  pinnately  divided  or  lobed,  the  divisions  often  toothed, 
cleft,  or  divided.  Calyx  2-5-toothed,  irregular.  Corolla 
2-lipped,  the  upper  arched  and  compressed  on  the  sides,  some- 
times with  a  beak;  the  lower  erect  at  base,  3-lobed,  and  with 
2  crests  above.  Stamens  4,  in  the  long  upper  lip. 

P.  densiflo'ra  Benth.  INDIAN  WARRIOR.  Leaves  twice  pinnately 
divided,  with  the  divisions  sharply  and  irregularly  incised.  Stem 
and  leaves  dark-red  when  young,  becoming  greener  with  age. 
Flowers  an  inch  long,  crimson,  in  a  dense  spike  that  lengthens  in 
fruit.  Common  in  western  and  middle  California. 


VHI.    MIM'ULUS,  Monkey  Flower 

Herbs,  or  one  species  shrubby,  with  opposite,  simple  leaves 
and  showy  flowers  on  axillary  peduncles.  Calyx  bell-shaped, 
5-toothed,  and  with  as  many  folds  and  angles,  often  oblique. 
Corolla  with  the  tube  included  in  the  calyx  and  the  border  with 
5  round,  spreading  lobes  arranged  so  that  2  form  the  upper  lip 
and  3  the  lower.  Within  the  tube  are  two  ridges  flattened  on 
top,  running  down  the  lower  side  of  the  throat.  Stamens  4, 
with  the  anther  cells  diverging.  Stigma  2-lobed,  with  spread- 
ing parts,  often  somewhat  shield-shaped.  When  an  insect 
alights  it  touches  the  stigma,  which  immediately  closes,  the 
2  lips  folding  together  ;  the  anthers  are  thus  exposed,  so  that 
the  insect  becomes  dusted  with  pollen.  This  can  be  observed 
by  touching  the  stigma  with  a  pencil. 

a.  M.  cardina'lis  Dougl.  RED  MONKEY  FLOWER.  Stout,'  2-4*ft. 
high,  viscid-pubescent.  Leaves  sessile,  ovate,  dentate,  2  in.  long. 
Corolla  scarlet,  2  in.  long,  with  all  the  lobes  except  the  upper  one  reflexed. 
Stamens  projecting  from  the  corolla.  This  grows  along  streams. 
Widely  distributed. 


152  KEY   AND   FLORA 

b.  M.  Lewis'ii  Pursh.     Perennial,  with  erect,  rather  slender  stems, 
1-2  ft.  high,  or  more.     Leaves  lanceolate-ovate,  with   the  margin 
finely  toothed.      Corolla   rose-red,  2   in.  long,  the  border  of  roundish, 
spreading  lobes.     Stamens  included  within  the  corolla.     This  is  one 
of  the  handsomest  species.     It  grows  in  shady,  moist  places  from 
British  Columbia  through  California,  in  the  mountains. 

c.  M.    brev'ipes   Benth.     Annual,    1-2   ft.   high,  viscid-pubescent. 
Leaves    lanceolate    to    linear,   1-4   in.   long.     Calyx  teeth  unequal, 
pointed.      Corolla  yellow,  1^  in.  long,  the  border  campanulate,  an  inch 
across,  with  rounded  lobes.     From  Monterey  southward. 

d.  M.  Bolan'deri  Gray.     Annual,  with  stems  about  a  foot  high,  viscid- 
pubescent.     Leaves  oblong,  1-2  in.  long.      Corolla   crimson,  an   inch 
long,  tubular,  with  the  border  slightly  spreading.     This  is  common  in 
the  foothill  region  of  the  Sierra  Nevada  through  California. 

e.  M.    moscha'tus    Dougl.      MUSK-PLANT.       Perennial,  with   low, 
spreading  stems,  soft-hairy,  musk-scented.      Corolla  light  yellow,  $  in. 
long.       This   grows    in  wet  place   and    roots   at    the  joints  of   the 
stem.     Widely  distributed. 

/.  M.  Langsdor'ffii  Don.  Annual  or  perennial,  the  former  slen- 
der, the  latter  stout,  growing  in  wet  places  and  rooting  at  the 
joints  of  the  lower  parts  of  the  stem.  Stem  leaves  round,  clasp- 
ing; root  leaves  on  petioles,  with  a  roundish  blade  at  the  top  and 
a  few  small  leaflets  below.  Corolla  yellow,  with  brown  or  red  spots, 
decidedly  2-lipped,  large,  from  1  to  1^  in.  long.  Widely  distributed 
and  extremely  variable. 

g.  M.  tricolor  Lindl.  (Euna'nus  Benth.).  Low,  with  spreading, 
leafy  branches.  Corolla  2  in.  long,  with  a  short,  slender  tube  and  wide 
border  of  almost  equal  lobes,  rose-purple,  marked  with  deep  crimson,  and 
with  yellow  throat.  This  is  a  very  beautiful  plant,  and  grows  in  low, 
damp  places.  From  middle  California  northward. 

h.  M.  Douglas'ii  Gray  (Euna'nus  Benth.).  Erect,  with  stems 
beginning  to  flower  when  an  inch  or  so  high.  Corolla  crimson, 
decidedly  2-lipped,  the  lower  Up  wanting,  or  much  shorter  than  the 
upper  Up ;  tube  from  1  to  1£  in.  long;  throat  funnel-form,  dilated. 
Throughout  California,  in  bloom  usually  very  early. 

i.  M.  glutino'sus  Wendland  (Dip'lacus  Nutt.).  Shrubby,  3-6  ft. 
high,  with  glutinous,  evergreen  foliage.  Leaves  opposite,  serrate, 
veiny.  Flowers  yellow  or  reddish,  large  and  showy,  solitary,  on  pedicels 
in  the  leaf  axils.  This  is  common  throughout  California,  and  has 
many  forms  regarded  as  species  by  good  botanists. 

^f.  M.  exilis  Dur.  Annual,  erect,  with  branched  stems  about  a 
foot  high,  leafy  and  soft-hairy,  somewhat  viscid,  flowering  from  the 
first.  Leaves  lanceolate,  sessile,  entire,  the  lower  longer  than  the 
upper  and  shorter  than  the  pedicels.  Calyx  ~~5-cleft,  bell-shaped, 
the  tube  without  angles  and  almost  without  nerves.  Corolla  a  little 


DICOTYLEDONOUS   PLANTS  153 

loti (/cr  than  the  calyx,  yellow,  /rif/t  nearly  equal  lobes  and  sometimes  some 
hrnn-ii  spots  in  the  throat.  Common  throughout  California  in  the  dry 
beds  of  streams. 


OROBANCHA'CEJE.     BROOM  RAPE  FAMILY 

Root  parasites,  tuberous,  pale  or  brownish  in  color,  with 
scales  in  place  of  -leaves.  Corolla  2-lipped.  Stamens  4,  in  2 
sets.  Ovary  1-celled,  with  parietal  placentae.  Seeds  many, 
very  small.  Style  long,  with  stigma  2-lobed.  Pod  splitting 
into  2  valves  when  ripe,  each  valve  with  1  or  2  placentae. 

APHYI/LON,  Cancer  Root 

Flowers  yellowish  or  purplish,  usually  on  peduncles.  Sta- 
mens included  in  the  somewhat  2-lipped  corolla.  Calyx  with 
5,  nearly  equal,  pointed  lobes.  Stigma  shield-shaped  or  with 
2  broad,  flat  lobes.  Placentae,  a  pair  to  each  valve.  Anther 
cells  deeply  separated  from  below,  awned  at  the  base. 

a.  A.  uniflo'rum  Gray.     Stem  very  short,  bearing  one  or  a  few 
slender  scapes  a  few  inches  high.     Flowers  violet  and  violet  scented, 
terminating  the  scapes.     Frequent  in  California  and  north  to  British 
Columbia. 

b.  A.  fascicula'tum  Gray.     Stems  rather  slender,  nearly  as  long  as 
the   numerous   fascicled    peduncles.     Flowers    brownish    or  yellowish. 
Widely  distributed. 


PLANTAGINA'CEJE.     PLANTAIN  FAMILY 

Herbs  with  the  leaves  and  peduncled  spikes  all  from  the 
root.  Corollas  papery,  4-cleft. 

PLANTA'GO,  Plantain 

Flowers  perfect,  each  with  a  bract  below.  Calyx  of  4  per- 
sistent sepals  free  from  the  ovary.  Corolla  greenish  or  dull 
white.  Stamens  2-4,  with  long  filaments.  Fruit  a  capsule 
opening  by  a  lid  which  falls  off,  carrying  with  it  the  placenta 
with  the  shield-shaped  seeds  attached. 


154  KEY   AND   FLORA 

a.  P.  ma'jor  L.     COMMON  PLANTAIN.     Leaves  large,   ovate,  5-7- 
ribbed,   the  petioles  channeled  on  the   upper   side.     A  wayside    weed, 
introduced. 

b.  P.  lanceola'ta  L.     Hairy.     Leaves  long,   lanceolate,   3-7-ribbed. 
Flowers  with  conspicuous  stamens  ;  at  first  in  a  head,  lengthening  to  a 
spike.     Introduced. 

c.  P.  marit'ima  L.     Smooth,  leaves  linear,  fleshy.     Spike  oblong. 
This  is  found  along  the  seashore. 

d.  P.  Patago'nica  Jacq.     A  small  annual  covered  with  white  silky 
wool.     Scape  2-3  in.  high.     Flowers  in  dense  oblong  spikes,  except 
in  very  small  plants,  where  they  form  a  head.     Widely  distributed. 
This  has  been  made  to  include  many  species  which  are  difficult  to 
distinguish. 

RUBIA'CEJE.     MADDER  FAMILY 

Herbs  or  shrubs  with  opposite,  entire  leaves  with  stipules  ; 
or  whorled  leaves  without  stipules.  Calyx  and  corolla  4-lobed, 
adnate  to  the  ovary.  Stamens  distinct,  alternate  with  the 
lobes  of  the  corolla  and  borne  on  its  tube.  Ovary  2-5-celled. 
Seeds  with  endosperm.  The  plants  yielding  coffee  and  quinine 
belong  to  this  family. 

I.    CEPHALAN'THUS,  Button  Willow 

Shrub  growing  near  ivater,  with  willow-like  leaves,  opposite 
or  whorled  ;  and  scale- like  stipules  within  the  petioles.  Flowers 
in  a  dense,  round  head.  Calyx  pointed  at  base,  4-toothed. 
Corolla  with  a  long,  slender  tube  and  a  small,  4-cleft  border. 
Stamens  short.  Style  long,  conspicuous,  with  a  cap-like  stigma. 
Capsule,  when  ripe,  splitting  from  the  base  upward  into  2-4, 
closed,  1-seeded  parts. 

C.  occidenta'lis  L.  Leaves  lanceolate,  3-5  in.  long.  Heads 
an  inch  in  diameter,  flowers  cream-color.  Common  along  streams 
throughout  California,  except  near  the  coast. 


II.    KELLOG'GIA 

Low,  slender,  much-branched  herbs.  Leaves  opposite,  with 
stipules  between  the  petioles.  Flowers  small,  dull  purple,  in 
loose  cymes.  Calyx  tube  somewhat  flattened,  covered  with 


DICOTYLEDONOUS   PLANTS  155 

stiff,  short  bristles.  Corolla  funnel-form  with,  narrow  lobes. 
Stamens  4,  on  the  throat  of  the  corolla.  Style  slender  ;  stig- 
mas 2,  thread-like.  Fruit  covered  with  hooked  bristles,  split- 
ting into  2  parts,  to  the  walls  of  which  the  seeds  adhere. 

K.  galioi'des  Torr.  This  grows  in  damp,  shady  places  in  the 
Sierra  Nevada  Mountains,  chiefly  northward. 

in.    GA'LIUM,  Bedstraw,  Cleavers 

Herbs  with  slender  stems,  whorled  leaves,  and  no  stipules. 
Flowers  small,  white  or  greenish.  Calyx  without  a  border. 
Corolla  wheel-shaped,  4-parted.  Stamens  short  ;  styles  2, 
short,  with  cap-like  stigmas.  Fruit  dry  or  fleshy,  of  2 
similar  rounded  parts  with  1  seed  in  each. 

*  Fruit  a  berry.     Perennials. 

a.  G.  Califor'nicum  Hook.  &  Arn.    Stems  low,  generally  growing  in 
bunches.    Leaves  thin,  oval,  with  a  bristle-tipped  apex:  margin  and  mid- 
rib with  stijf  hairs.     Fruit  pearly  white  when  ripe,  turning  black  when 
dried,  smooth,  on  recurved  pedicels.     Common  from  Sari  Francisco 
southward. 

b.  G.  Nuttal'lii  Gray.    Shrubby,  climbing  over  the  bushes,  with  a  tangled 
mass  of  slender  sterns  which  are  minutely  spiny  on  the  angles.     Oom- 
mon  throughout  California  near  the  coast. 

c.  G.    Andrews'!!   Gray.     Low,    densely    matted,    nearly  smooth, 
with    leaves    bright,    shining    green,    crowded,    somewhat    spine-tipped. 
Flowers   dio3cious,    the    sterile   in    few-flowered   cymes,    the    fertile 
solitary.     The   dead  stems  and  leaves   are   persistent  and  usually 
become  white. 

**  Fruit  dry. 

d.  G.  Apari'ne  L.     Annual,  climbing  by  the  reflexed  prickles  of 
the  stem  and  leaves.     Fruit  on  straight  pedicels,  densely  covered  with 
hooked  prickles  forming  a  bur.     Common. 

e.  G.  triflo'rum  Michx.     WALDMEISTER.     Stems  with  the  odor  of 
vanilla  when  dry,  weak,  spreading  on  the  ground.     Leaves  6  in  a 
whorl,  elliptical,  acute  at  both  ends,  having  a  few  short,  reflexed 
prickles   on    the    margins    and    midribs.      Peduncles  few,   3-forked; 
flowers  greenish  white,  on  spreading  pedicels.     Fruit  covered  with 
slender,  hooked  bristles.     This  grows  in  the  woods  from  San  Fran- 
cisco northward. 


156  KEY   AND   FLORA 

/.  G.  borea'le  L.  Erect,  smooth,  leafy,  branched.  Leaves  in 
fours,  linear  to  lanceolate,  obtuse.  3-nerved.  Flowers  white,  perfect, 
in  a  terminal  panicle.  Fruit  small,  hispid  at  first,  smooth  when  ripe. 
In  the  mountains  northward.  Summer. 


CAPRIFOLIA'CEJE.     HONEYSUCKLE  FAMILY 

Shrubs  or  shrubby  vines  (rarely  herbs)  with  opposite  leaves 
without  stipules.  Flowers  perfect;  regular  or  irregular.  Calyx 
5-toothed,  adnate  to  the  inferior  ovary.  Corolla  4  or  5  cleft. 
Stamens  distinct,  as  many  as  the  corolla  lobes  and  alternat- 
ing with  them.  Ovary  2-5-celled.  Fruit  a  berry,  drupe  or 
capsule. 

I.    SYMPHORICAR'POS,  Snowberry 

Low,  branching  shrubs,  with  leaves  usually  entire  (some- 
times on  young  shoots  lobed  at  the  base).  Flowers  in  axil- 
lary or  terminal  spikes  or  clusters  with  2  bracts  under  each 
flower.  Calyx  5-toothed,  persisting  on  the  fruit.  Corolla 
bell-shaped,  5  or  4  lobed.  Fruit  a  roundish,  white  berry  con- 
taining 2  bony  nutlets.  The  berries  are  usually  densely  clus- 
tered at  the  ends  of  the  branchlets. 

a.  S.  racemo'sus    Michx.     Erect  shrubs,    smooth  or  with   the   lower 
face  of  the  leaves  pubescent.     Flowers  in  terminal,  short  and  inter- 
rupted  spike-like   racemes,    or    some   solitary   in   the    upper  axils. 
Corolla  very   hairy   within  at  the   base   of   the   lobes.     Style  and 
stamens  short.     Widely  distributed. 

b.  S.    mollis    Nutt.     Low,,  diffusely  spreading,  softly   and   densely 
pubescent.     Leaves  oval,  small.     Flowers  few  in  terminal  clusters 
or  in  the  upper  axils.     Corolla  short  and  broad,  but  little  bearded 
inside.     Throughout  California. 

II.    LONIC'ERA,  Honeysuckle,  Twin-berry 

Twining  or  erect  shrubs  with  entire  leaves  (sometimes 
lobed  on  short  shoots),  the  upper  united  around  the  stem  in 
some  species.  Flowers  many  in  interrupted  spikes,  or  axillary 
in  pairs  which  are  sessile  in  an  involucre.  Calyx  minutely 
5-toothed.  Corolla  tubular,  funnel-form,  or  oblong  bell-shaped, 
with  the  border  5-lobed ;  or  2-lipped,  ivith  4  lobes  forming  the 


DICOTYLEDONOUS  PLANTS  157 

upper  and  1  the  lower  lip.  Ovary  2  or  3  celled,  with  numer- 
ous ovules  in  each  cell.  Style  slender,  tipped  by  a  cap-like 
stigma. 

a.  L.  hispid'ula  Dougl.      Twining,  with  the  broad  floral  leaves, 
uniting  around  the  stem,  the  others  elliptical,  all  except  the  lowest 
with  broad  stipule-like  appendages,  all  bluish  green  and  pale.     Spikes 
of  3-6   whorls  of  pink  flowers  with  the  corollas  2-iipped.     Fruit  a  red 
berry,  somewhat  riscid.     Along  the  coast. 

b.  L.  interrup'ta  Benth.     Stoutish,  erect  and  bushy,  less  disposed 
to    twine,    branches    covered    with    shining    white    bark.      Leaves 
pale-green,  nearly  round,  all  without  stipules,  several  of  the  upper 
pairs    uniting.       Spikes    of    several    interrupted    whorls.       Flowers 
yellow,  smooth.     Inner  Coast  Mountains  and  foothills  of  the  Sierra 
Nevada. 

c.  L.  involucra'ta  Banks.     Shrubs  with  stems  erect,  never   twining, 
and  leaves  never  united.     Flowers  in  pairs  on  an  axillary  peduncle, 
each    pair    contained    in    a   leafy    involucre    of   2    bracts.     Corolla 
yellowish,  funnel-form,  swollen  at  the  base.     Berries  close  together, 
black  when  ripe,  the  involucre  becoming  dark  red,  with  the  lobes  reflexed. 
Widely  distributed. 

d.  L.  cilio'sa  Poir,     Stems  low,  or  climbing.     Leaves  broadly  ovate, 
glaucous  beneath,  generally  smooth  except  for  the  ciliate  margin ; 
the    uppermost  one  or  two  pairs  united  to  form  a  disk.     Whorls 
of  flowers    1-3,   generally  terminal  but  sometimes  from  the  lower 
leaf  axils.     Corolla  smooth,  an  inch  or  more  long,  trumpet-shaped,  scarlet 
without,  yellow  within ;  the  tube  swollen  on  one  side  near  the  base ;  the 
border   slightly   2-lipped.      From    the   Sierra  Nevada    Mountains    of 
middle  California  to  British  Columbia. 


III.    SAMBU'CUS,  Elder 

Shrubs  or  small  trees  with  pinnately  compound  leaves  of 
5-11  serrate  leaflets.  Flowers  small,  white,  in  compound 
cymes.  Corolla  wheel-shaped  or  urn-shaped,  with  5  lobes. 
Stigmas  and  cells  of  the  ovary  3-5.  Fruit  consisting  of 
"berries,"  which  are  really  drupes. 

a.  S.  glau'ca  Nutt.      Cymes  large  and  flat.      Berries  dark-blue, 
with  a  dense  bloom.     This  blooms  in  summer  and  is  common  in 
middle  and  southern  California. 

b.  S.  callicar'pa  Greene.    Cymes  ovate.    Berries  red,  rarely  yellow. 
This  blooms  in  spring  and  is  found  only  in  ravines  or  along  streams. 
Northward. 


158  KEY   AND   FLORA 


CUCURBIT A'CE.aL     GOURD  FAMILY 

Herbs,  with  succulent  stems,  climbing  by  tendrils.  Leaves 
palmately  lobed,  without  stipules.  Flowers  monoecious  or 
dioecious.  Calyx  adnate  to  the  ovary,  with  5  lobes  or  teeth. 
Corolla  with  petals  more  or  less  united.  Ovary  3-5-celled, 
stigmas  3-5-lobed.  Fruit  dry  or  fleshy.  This  family  con- 
tains the  Squash,  Melon,  Cucumber,  Pumpkin,  and  Gourd. 

ECHINOCYS'TIS    (MEGARRHFZA,   MICRAMPELIS) ,   Big  Root,    Chilicothe 

The  California  species  are  rapidly  growing  vines,  springing 
from  enormous  fleshy  roots.  Flowers  small,  white,  monoe- 
cious. Sterile  flowers  in  racemes,  at  the  base  of  which  are 
the  solitary  fertile  flowers  (often  they  are  wanting).  Corolla 
wheel-shaped  or  bell-shaped.  Fruit  round  or  oblong,  spiny, 
the  cells  within  with  fibrous  walls.  Seeds  round,  flattened. 
Cotyledons  thick,  not  coming  above  the  ground  in  germi- 
nation. 

a.  E.    faba'cea    Naudin.     Flowers    yellowish    white,    numerous; 
fruit  round,  densely  covered  with  long,  stout  spines.     Seeds  4.     This  is 
the  commonest  species. 

b.  E.  ma'ra  Cogn.     Flowers    larger   and   purer   white   than   the 
above,  less   numerous ;  fruit  pointed   at  both  ends,  sparingly  covered 
with  spines.     This  is  a  more  luxuriant  plant  than  the  preceding,  and 
is  less  common,  found  chiefly  around  San  Francisco. 

c.  E.  Orego'na  Torr.     Fruit  ovate-oblong,  1-2  inches  long,  sparingly 
clothed  with    soft    spines,    with    3-4    cells,   each  3-seeded.     Fertile 
flowers  with  abortive  stamens.     This  is  common  in  Washington. 

d.  E.  macrocar'pa  Greene.     Fruit  oblong,  densely  covered  with  long, 
rather  soft,  stout  spines.     Seeds   several,   more   than  4-     Central  and 
southern  California. 


VALERIANA'CE.a£.     VALERIAN  FAMILY 

Herbs  with  a  disagreeable  odor,  opposite  leaves  without 
stipules,  arid /Sowers  in  cymes.  Calyx  tube  adnate  to  the 
ovary,  teeth /none,  or  becoming  feathery.  Corolla  with  a  tube 
and  a  2-lipped  border.  Stamens  1-3  on  the  corolla.  Style 


DICOTYLEDONOUS   PLANTS  159 

and   filaments    slender.     Stigma  entire    or  minutely  3-cleft. 
Fruit  an  akene  with  the  seed  hanging. 

VALERIANEI/LA 

Low  annuals  with  stems  generally  simple,  and  flowers  in 
cymes  forming  whorls  at  intervals  along  the  stem.  Corolla 
rose-color,  small,  with  tube  swollen  at  base,  or  with  a  spur 
and  a  2-lipped  border.  Calyx  without  a  border.  The  species 
are  few  but  somewhat  difficult  to  distinguish. 

VALERIA'NA,  Valerian 

Perennials,  with  simple  steins.  Flowers  small,  in  terminal 
panicles  or  cymes.  Corolla  white  or  pale  pink.  Calyx  limb  of 
5-15  bristle-like  lobes,  which  are  curled  up  when  the  flower  is  in 
i,  but'  sjtread  out,  becoming  feathery  in  fruit.  Stamens  3. 


a.  V.  sylvat'ica  Richardson.  Stems  erect,  a  foot  or  two  high, 
from  running  rootstocks.  Root  leaves  simple,  on  long,  slender 
petioles,  or  compound.  Stem  leaves  pinnately  divided  into  3-11 
leaflets,  which  are  entire  or  sparingly  toothed.  Cymes  closely  flow- 
ered, more  open  in  fruit.  Flowers  light-pink  or  white,  \  in.  long. 
In  the  mountains,  from  middle  to  great  elevations.  Summer. 


CAMPANULA'CE^.     HAREBELL  FAMILY 

Herbs  with  milky  juice.  Leaves  alternate,  without  stipules. 
Calyx  adnate  to  the  ovary,  persistent.  Corolla  usually  blue, 
withering  and  persisting.  Stamens  generally  5,  inserted  at 
the  base  of  the  corolla  and  alternate  with  its  lobes,  ripening 
before  the  pistil.  Stigma  with  2-5  lobes,  which  do  not 
expand  until  some  time  after  the  flower  opens.  Style  hairy, 
so  as  to  collect  the  pollen.  Capsule  2-5-celled,  with  axillary 
placenta,  opening  by  holes  at  the  top  or  on  the  sides. 

I.    GITHOP'SIS 

Low,  simple  or  branched  annuals,  with  small  blue  flowers. 
Calyx  with  a  10-ribbed  tube  and  5  long,  narrow,  leaf-like  lobes. 


160  KEY  AND  FLORA 

Corolla  tubular  bell-shaped,  5-lobed.  Stamens  with  short  fila- 
ments dilated  at  the  base.  Pistil  with  three  stigmas  and  a 
3-celled  ovary.  Capsule  long  and  narrow,  firm  in  texture  and 
strongly  ribbed,  crowned  by  the  persistent  calyx  lobes,  opening  by 
a  hole  at  the  top  left  by  the  falling  away  of  the  base  of  the  style. 

G.  specularioi'des  Nutt.  Leaves  linear,  sessile,  coarsely  toothed. 
Corolla  deep  blue  with  a  white  center.  Flowers  on  short  peduncles 
at  the  ends  of  the  stems  and  branches.  This  is  widely  distributed, 
but  not  conspicuous. 

II.    CAMPANULA,  Harebell 

Perennial  herbs  with  determinate  inflorescence.  Calyx 
lobes  narrow.  Corolla  blue,  bell-shaped,  5-lobed.  Stamens 
5,  with  the  filaments  dilated  at  base.  Capsule  short  and 
roundish,  3-5-celled,  opening  on  the  sides  or  near  the  base  by 
3-5  small,  uplifted  values,  leaving  round  perforations. 

a.  C.  prenanthoi'des  Durand.     Stems  clustered,  slender,  a  foot  or 
two  high.     Leaves  ovate-oblong,  coarsely  serrate,  those  on  the  stem 
mostly  sessile,  the    lower  ones  on   short    petioles.     Pedicels   shorter 
than  the  flowers.     Calyx  lobes  much  shorter  than  the  corolla.     Style 
conspicuously  extending  beyond  the  corolla.     This  is  found  in  moist, 
shady  places  in  the  foothills  of  the  Sierra  Nevada  Mountains  and 
in  redwood  forests  along  the  coast. 

b.  C.  Scou'leri  Hook.      Stems    slender,  branching,    a    foot   or    so 
high,  smooth  or  slightly  pubescent.     Leaves  ovate,  pointed,  sharply 
serrate,  tapering  to  a   petiole.     Flowers   on    long  pedicels,  somewhat 
panided.     Corolla  oblong  in  bud,  exceeding  the  slender  calyx  lobes, 
deeply  5-cleft,  with  ovate-oblong  lobes.    In  shady  woods  from  middle 
California  north  to  British  Columbia. 


LOBELIA'CE^.     LOBELIA  FAMILY 

Low  herbs  with  milky  juice.  Leaves  simple,  alternate. 
Flowers  scattered  or  in  racemes.  Calyx  5-lobed,  adnate  to  the 
ovary  or  only  to  its  lower  half.  Corolla  irregular,  apparently 
2-lipped,  inserted,  with  the  free  part  of  the  calyx,  on  the 
ovary.  Stamens  5,  alternate  with  the  lobes  of  the  corolla. 
Filaments  united  into  a  tube  at  the  base  and  usually  even  to 
the  top.  Style  1,  stigma  2-lobed.  Ovary  2-celled  with  an 


DICOTYLEDONOUS   PLANTS  161 

axillary  placenta,  or  1 -celled  with  parietal  placentae.     Capsule 
many-seeded,  the  seeds  with  endosperm. 

DOWNIN  GIA,  GARDENERS'  NAME  Clinto'nia 

Low  and  spreading  smooth  annuals,  growing  in  low,  wet 
places  that  gradually  dry  ("  hog  wallows  ").  Leaves  small, 
sessile,  entire,  becoming  bracts  above.  Calyx  tube  and  ovary 
very  long  and  slender,  becoming  twisted,  the  divisions  of  the 
calyx  linear  and  leaf-like.  Corolla  2-lipped,  the  smaller  lip 
of  2  narrow,  recurved,  or  spreading  divisions  ;  the  other  broad, 
3-lobed,  deep  blue,  with  a  white  or  yellow  center.  Filaments 
and  anthers  united  into  a  curved  tube.  Capsule  long  and 
slender,  becoming  1-celled,  splitting  along  the  sides  but  closed 
at  the  top. 

a.  D.  eregans  Torr.     Low,  with  ovate  to  lanceolate  leaves,  acute. 
The  smaller  lip  of  the  corolla  of  2  lanceolate  divisions;  the  other  3-lobed, 
blue  with  a  white  center.     Northern  California  to  Washington  and 
Idaho. 

b.  D.  pulchella  Torr.     Stems  3-6  in.  high.     Leaves   lanceolate, 
obtuse.     The  smaller  lip   of  the  corolla  with  2  oblong  divisions;  the 
other  broad,  3-lobed,  azure  blue,  with  a  large  white  or  yellow  spot  in 
the  center.     Through  middle  California  to  Oregon. 

COMPOSITE.     COMPOSITE  FAMILY 

Flowers  in  a  dense  head,  on  a  common  receptacle,  sur- 
rounded by  an  involucre  composed  of  many  bracts  (/.  Fig.  133  ; 
e.  Fig.  110),  with  usually  5  stamens  inserted  on  the  corolla  ; 
the  anthers  united  into  a  tube  which  surrounds  the  style 
(/.  Fig.  153 ;  e.  Fig.  131).  Calyx  with  its  tube  adnate  to  the 
ovary,  the  limb  sometimes  wanting,  when  present  taking  the 
form  of  scales,  bristles,  etc.,  known  as  pappus.  Corolla  either 
strap-shaped,  2-lipped,  or  tubular  (/.  Fig.  147 ;  e.  Fig.  110),  in 
the  first  case  often  5-toothed,  in  the  last  usually  5-lobed.  Style 
2-cleft  above.  Fruit  an  akene,  often  provided  with  means  of 
transportation  (/.  Fig.  267;  e.  Figs.  174, 178, 179).  The  largest 
family  of  flowering  plants  and  among  the  most  specialized  for 
insect  fertilization.  The  genera  here  included  belong  to  the 


162  KEY   AND   FLORA 

three  suborders  :  I,  LIGULIFLORJE,  the  corollas  all  strap-shaped 
and  flowers  all  perfect ;  II,  LABIATIFLOR^,  corollas  of  all  or 
only  the  perfect  flowers  2-lipped  ;  III,  TUBULIFER^:,  corolla 
of  the  perfect  flowers  tubular  and  5-lobed.  To  the  latter 
belong  nine  tribes,  eight  of  which  are  represented  by  the 
plants  included.  The  figures  refer  to  illustrations  in  Part  I. 

KEY  TO  THE  SUBORDERS  AND  TRIBES  OF  COMPOSITE 

SUBORDER  I.  —  LIGULIFLO'R^E.  All  flowers  ray  flowers. 
Herbs  with  milky  juice. 

SUBORDER  II.  —  LABIATIFLO'R^E.  Corollas  of  all  or  only 
the  perfect  flowers  2-lipped.  Receptacle  naked  ;  anthers  with 
conspicuous  tails ;  style  branches  short,  smooth,  without 
appendages. 

SUBORDER  III.  —  TUBULIFLO'RTE.  Flowers  tubular,  the 
outer  ones  only  with  rays,  or  the  ray  flowers  entirely  wanting. 
The  accompanying  figures  are  to  illustrate  the  descriptions  of 
the  several  tribes.  They  represent  the  style  branches  and 
anthers  as  seen  when  magnified* 

Tribe  1.  EUPATORTA'CE^E.  Heads  without  rays.  Flowers 
all  perfect,  never  yellow.  Anthers  without  tails.  Style 
branches  club-shaped. 

Tribe  2.  ASTEROI'DE^:.  Heads  with  or  without  rays. 
Anthers  without  tails.  Style  branches  of  disk  flowers  flat, 
tipped  with  an  appendage.  Leaves  all  alternate. 

Tribe  3.  INULOI'DEJE.  Heads  usually  without  ray  flowers. 
Anthers  with  tails.  Style  branches  of  perfect  flowers  neither 
truncate  nor  tipped  with  an  appendage. 

Tribe  4.  AMBRO'SLS:.  Heads  without  ray  flowers.  Anthers 
distinct,  not  united.  Style  abortive,  truncate.  Corolla  of 
female  flowers  rudimentary  or  wanting.  Pappus  none. 

Tribe  5.  HELIANTHOI'DEJE.  Anthers  without  tails.  Style 
branches  of  perfect  flowers  truncate  or  tipped  with  an  append- 
age. Bracts  of  the  involucre  not  papery.  Pappus  never 
capillary.  Receptacle  with  chaffy  scales  mixed  among  the 
flowers  or  only  near  those  on  the  outside. 


DICOTYLEDONOUS   PLANTS 


163 


Tribe  6.  HELENIOI'DE^;.  Similar  to  Helianthoidece,  but 
there  are  no  chaffy  scales  on  the  receptacle. 

Tribe  7.  ANTHEMOI'DE^E.  Similar  to  Helianthoidece,  but 
the  involucre  consists  of  papery  bracts  in  regular  rows,  the 
pappus  is  a  short  crown  or  wanting,  and  the  receptacle  rarely 
has  chaffy  scales  mixed  with  the  flowers. 


\ 


I 


FIG.  5. 


FIG.  6. 


FIG.  7. 


FIG.  8. 


FIG.  9. 


FIG.  10. 


FIG.  11. 


Fig 


£.  5.  Anthers  with  tails  (c,  tails).— Fig.  6.  Anthers  without  tails  (<l,  base  of 
anthers).— Fig.  7.  Style  and  stigma  of  Tribe  9.  —  Figs.  8, 9.  Flat  style  branches 
tipped  with  an  appendage  (a,  appendages).  —  Fig.  10.  Style  branches  of  7V//« 
3.  —  Fig.  11.  Truncate  style  branches.  —  e,  the  part  of  the  anthers  containing 
the  pollen;  b,  the  stigmatic  part  of  the  style. 


Tribe  8.  SENECIONI'DE.E.  Similar  to  Helianthoidece,  but 
the  pappus  is  abundant  and  capillary  and  the  receptacle  is 
destitute  of  chaffy  scales.  The  bracts  of  the  involucre  are 
generally  in  a  single  series. 


164  KEY   AND   FLORA 

Tribe  9.  CYNAROI'DE^E.  Anthers  either  with  tails  or  arrow- 
shaped.  Style  branches  without  tips  or  appendages,  often 
united  at  the  apex.  Corollas  all  tubular,  with  long,  narrow, 
linear  divisions.  Eeceptacle  densely  bristly. 


SUBORDER  I.  —  LIGULIFLO'R^E 

All  the  flowers  ray  flowers.  Herbs  with  milky  juice.  The 
flowers  are  generally  closed  in  the  afternoon. 

I.     CICHO'RIUM,  Chicory 

Perennial  herbs  with  long,  spreading  branches.  Leaves 
radical  and  alternate,  toothed  or  pinnatifid.  Heads  an  inch 
or  more  in  diameter,  bright  blue,  in  the  axils  of  the  leaves. 
Bracts  of  the  involucre  in  2  series,  firmly  enclosing  the  ripe 
akenes.  Pappus  1  or  2  series  of  short,  obtuse  scales. 

C.  In'tybus  L.  This  is  very  beautiful  in  the  summer  and  fall. 
The  stems  become  garlands  of  bright  blue  flowers.  It  has  escaped 
from  cultivation. 

II.    HYPOCH^'RIS,   Cat's  Ear 

Annual  or  perennial  herbs,  with  the  leaves  all  radical,  and 
forming  a  rosette  at  the  base  of  the  stem.  Stems  naked, 
branching,  terminated  by  heads  of  yellow  flowers.  Bracts  of 
the  involucre  in  rows ;  receptacle  with  chaffy  scales  that 
fall  soon.  Pappus  consisting  of  1  row  of  feathery  hairs  and 
an  outer  row  of  short,  stiff  bristles.  The  two  species  are 
introduced. 

a.  H.  gla'bra  L.     Annual.     Sterns  several,  slender,  erect.     Heads 
rather  small,  with  the   involucres  as  long  as  the  flowers.     Widely 
distributed. 

b.  H.  radica'ta  L.     Perennial.     Stems  many.     Heads  much  larger, 
the  involucres  shorter  than  the  flowers.     Not  quite  so  common  as 
the  preceding. 

m.    TRAGOPO'GON,   Oyster  Plant,  Salsafy 

Smooth  herbs  from  fleshy  tap-roots.  Leaves  thin,  lax, 
sessile,  tapering  to  a  long  point.  Heads  large,  with  purple 


DICOTYLEDONOUS   PLANTS  165 

flowers,  bracts  of  the  involucre  in  one  series,  united  at  the 
base  and  generally  longer  than  the  flowers.  Akenes  with  long 
beaks  and  plentiful  brownish  pappus  hairs,  that  are  feathery, 
with  naked  tips,  and  so  numerous  that  they  interlace. 

T.  porrifolius  L.  This  is  common,  having  escaped  from  culti- 
vation. The  large  purple  heads  are  on  thick,  hollow  stems.  The 
flowers  soon  fade. 

IV.     MICRO'SERIS 

Low  herbs,  with  leaves  chiefly  radical  and  heads  of  yel- 
low flowers  on  naked  stems,  mostly  nodding  before  opening. 
Akenes  ribbed,  truncate  at  apex ;  pappus  of  several  papery 
scales  that  spread  in  fruit.  The  species  are  rather  difficult  to 
distinguish. 

V.     STEPHANOME'RIA 

Herbs  with  smooth,  almost  leafless  branches.  Heads  of  pink 
flowers,  numerous,  sessile,  scattered  along  the  naked  stems, 
in  bloom  only  in  the  morning.  Akenes  5-ribbed,  truncate  at 
both  ends,  with  plumose  bristles. 

S.  virga'ta  Benth.  This  is  simple  or  widely  branched,  and  often 
grows  to  a  height  of  several  feet.  The  bracts  of  the  involucre  are 
in  a  single  row,  with  a  few  loose  ones  at  base.  This  is  in  bloom 
through  the  summer  and  fall.  Widely  distributed. 


VI.    RAFINES'QUIA 

Annual,  smooth  herbs,  with  leafy,  branching  stems,  and 
heads  of  white  or  flesh-colored  flowers  an  inch  in  diameter, 
terminating  the  branches.  Akenes  terete,  gradually  nar- 
rowed to  a  slender  beak.  Pappus  ivhite,  cobwebby. 

R.  Califor'nica  Nutt.  This  is  the  common  species,  which  is  widely 
distributed  but  seldom  abundant. 


VII.     MALACOTHRIX 

Generally  annual,  with  leafy  or  scape-like  stems.  Flowers 
various.  The  akenes  have  the  apex  developed  into  a  crown,  and 
the  silky  pappus  bristles  falling  in  a  ring. 


166  KEY   AND   FLOE  A 

a.  M.  Courteri   Gray.     Erect,  with   glaucous   stems  and  leaves. 
The  bracts  of  the  involucre  are  broad,  blunt,  shining,  and  papery,  with  a 
green  midrib,  loosely  arranged  in  several  rows ;  the  flowers  are  white, 
turning  pink  in  drying  or  fading.     This  is  one  of  the  most  notice- 
able annuals  of  the  San  Joaquin  Valley. 

b.  M.  Calif  or'  nica  DC.     Annual,  with  the  heads  large,  solitary  at  the 
ends  of  scape-like  stems,  the  leaves  all  radical  and  pinnately  parted 
into  narrow,  linear  divisions.     Flowers  yellow.     The  scales  of  the 
involucre  are  linear  and  loosely  ranked.      Pappus  of   2   persistent 
bristles  and    minute-pointed  teeth  between.     This  generally  grows 
in  sandy  soil,  and  is  most  common  in  southern  California. 

c.  M.  saxa'tilis  T.  &  G.     Perennial,  with  leafy,  branching  stems, 
1-4  ft.  high.     Leaves  entire  or  cut  into  slender  divisions  from  lan- 
ceolate to  thread-like,  in  some  varieties  quite  fleshy.     Heads  many- 
flowered,  an  inch  or  less  in  diameter,  terminating  the  branchlets, 
white  turning  to  rose-color.     Involucres  of  numerous,  narrow  bracts 
extending   down  onto  the  peduncle.     Akenes  ribbed,  the  summit 
with  a  border  of  minute  white  teeth.     This  is  common  in  southern 
California,  blooming  in  summer  and  fall,  and  in  several  varieties 
from  the  seacoast  to  the  higher  hills. 


VIII.    TROX1MON,  Western  Dandelion 

Perennial  herbs,  with  radical  leaves  and  heads  of  yellow 
flowers  on  hollow  scapes.  Akenes  with  smooth  ribs  and  a  long 
beak  ;  the  bristles  of  the  capillary  pappus  falling  singly.  The 
involucre  consists  of  bracts  in  several  series. 


IX.    TARAX'ACUM,  Dandelion 

Similar  to  Troximon.  The  akenes  have  a  long  beak  and  the 
bristles  of  the  pappus  persist  on  the  akene.  The  only  species 
is  not  native. 

X.    SON'CHUS,  Sow  Thistle 

Herbs  with  spiny  leaves,  and  erect,  branching  stems.  Heads 
with  the  bracts  in  several  series,  and  flowers  yellow.  Akenes 
flat,  with  soft,  silky-white,  capillary  pappus. 

a.  S.  olera'ceus  L.  Leaves  pinnatifid,  tipped  with  soft  spiny 
teeth,  tapering  from  an  auricled  base  to  a  long  point,  the  auricles 
acute,  akenes  rough.  This  is  a  very  common  introduced  weed. 


167 

b.  S.  as'per  Vill.  Erect,  more  robust  than  the  preceding,  with 
leaves  decidedly  spiny  ;  the  auricles  of  the  leaves  are  rounded.  The 
akenes  are  smooth  with  sharp  edges.  This  is  less  common  than  the 
preceding. 

SUBORDER  II.  —  LABIATIFLO'RAE 

Corollas  of  all  or  only  the  perfect  flowers  2-lipped.  Recep- 
tacle naked ;  anthers  with  conspicuous  tails  ;  style  branches 
short,  smooth,  without  appendages. 

PERE'ZIA 

Herbs  with  alternate,  rigid  leaves.  Flowers  solitary  or  in 
panicles,  purple  or  white,  all  perfect.  Involucre  with  leathery 
scales  in  several  ranks.  Corolla  with  slender  tube  ;  the  outer, 
longer  lip  3-toothed  ;  the  inner  2-toothed  or  2-cleft.  Anthers 
with  long,  naked  tails  at  base  and  a  lanceolate  appendage  at 
apex.  Akenes  usually  glandular.  Pappus  of  rough,  hair-like 
bristles. 

P.  microceph/ala  Gray.  Stems  2-3  ft.  high,  branching,  glandular 
at  the  upper  part,  leafy  to  the  top.  Leaves  thin,  veiny,  oblong  to 
ovate,  clasping  by  a  heart-shaped  base  ;  margin  with  minute  spine- 
tipped  teeth.  Heads  numerous  in  corymbs  at  the  ends  of  the 
panicled  branches.  Flowers  rose-purple.  This  is  common  in  south- 
ern California,  blooming  in  the  summer  and  fall. 


SUBORDER  III.  —  TUBULIFLO'RJE 

Flowers  tubular,  the  outer  ones  only  with  rays,  or  the  ray 
flowers  entirely  wanting. 

Tribe  1.  EUPATORIA'CE^E.  Heads  without  rays.  Flowers 
all  perfect,  never  yellow.  Anthers  without  tails.  Style 
branches  club-shaped. 

I.     BRICKEI/LIA 

Herbs  or  low  shrubs,  with  opposite  or  alternate,  veiny 
leaves.  Heads  few-  to  many-flowered  ;  bracts  of  the  involucre 
somewhat  papery,  in  regular  rows,  nerved  with  parallel  rows 
or  veins.  Receptacle  naked.  Corollas  slender,  5-toothed  at 


168  KEY   AND    FLORA 

summit,  with  the  teeth  glandular  on  the  outside.  Pappus  a 
single  row  of  feathery  or  rough  bristles.  Flowers  white, 
greenish  or  pinkish. 

B.  Califor'nica  Gray.  Stems  2-3  ft.  high,  with  wand-like  branches, 
usually  growing  in  bunches.  Leaves  ovate,  obtuse,  crenate-dentate, 
about  an  inch  long.  Heads  in  axillary  clusters,  together  forming 
an  interrupted,-  erect  panicle.  Common  through  California,  often 
growing  in  the  gravelly  beds  of  streams.  Blooming  in  the  summer 
and  fall. 

Tribe  2.  ASTEROI'DE^.  Anthers  without  tails.  Style 
branches  of  disk  flowers  flat,  tipped  with  an  appendage. 
Leaves  all  alternate. 


II.     GRINDE'LIA,  Gum  Plant 

Coarse,  resinous  herbs,  with  toothed  leaves,  large  heads  with 
yellow  rays  and  disk,  in  bud  covered  with  a  drop  of  milky-look- 
ing resin.  Scales  of  the  broad  involucre  in  several  series,  with 
green,  spreading  tips.  Akenes  compressed.  Pappus  of  a  few 
bristles  that  fall  off  easily.  This  is  the  most  recommended 
cure  for  the  poisoning  from  Poison  Oak.  There  are  several 
species  difficult  to  determine. 

III.     LESSIN'GIA 

Much-branched,  slender-stemmed  plants,  with  numerous 
small  rayless  heads  of  yellow,  purple,  or  white  flowers  on  slender 
peduncles,  the  corollas  of  the  outside  flowers  having  the  lobes 
usually  elongated  and  unequal.  Involucre  silky-hairy.  Pappus 
a  single  row  of  stiff  rough  bristles.  They  bloom  in  the  sum- 
mer, and  the  flowers  deck  the  stems  like  small  rosettes. 

a.  L.    Germano'rum    Cham.      YELLOW    LESSINGIA.      Low    and 
spreading,  with  heads  of  yellow  flowers.     Outer  corollas  with  lobes 
unequal. 

b.  L.  lepto'clada  Gray.     Stems  from  a  few  inches  to  2  ft.  high, 
much  branched,  with  numerous,  very  slender,  smooth  branchlets,  termi- 
nated by  the  heads  of  lilac  or  ivhite  flowers.     Lobes  of  the  corolla 
equal,  the  tube  as  long  as  the  pappus.     This  is  widely  spread  and 
very  variable.     The  lower  leaves  are  frequently  dry  when  the  plant 


DICOTYLEDONOUS   PLANTS  169 

is  in  bloom.  They  are  spatulate,  toothed,  white-woolly;  the  upp«T 
are  triangular-ovate  and  closely  sessile.  Western  and  central  Cali- 
fornia. Variable. 

IV.     CHRYSOP'SIS,  Golden  Aster 

Perennial  herbs  with  many  stems  from  the  root,  very  leafy, 
with  alternate,  sessile  leaves.  Heads  either  ivith  or  without 
rays,  solitary  or  in  corymbs.  Bracts  of  the  involucre  in 
several  series,  either  with  or  without  papery  margins,  and 
without  green  tips.  Flowers  yellow.  Akenes  compressed, 
hairy.  Pappus  usually  double  ;  the  inner  a  row  of  long,  rough, 
rusty  bristles;  the  outer  a  row  of  short,  narrow,  chaffy  scales 
or  bristles. 

a.  C.  sessiliflo'ra  Nutt.     Hairy  or  soft-wroolly,  with  stems  a  foot 
or  so  high.     Heads  about  an  inch  in  diameter,  with  rays.     There 
are  several  varieties  of  this  which  are  considered  species  by  some 
botanists.     Common,  and  in  bloom  all  the  year. 

b.  C.  Orega'na  Gray.     Stems  spreading,  branched  above,  rough- 
hairy.     Heads  numerous  without  rays,  the  involucre  almost  equal- 
ing  the    flowers.     The    outer   pappus    consists    of   slender   bristles 
rather  than  chaffy  scales.     This  is  found  in  dry  stream-beds  through 
middle  California  to  Washington. 


V.    APLOPAP'PUS 

Herbs  or  shrubs,  with  numerous  heads  of  yellow  flowers, 
the  outer  ones  having  rays  (with  one  or  two  exceptions). 
Bracts  of  the  involucre  in  several  series.  Akenes  narrow,  with 
pappus  in  one  row.  Receptacle  honeycombed. 

a.  A.  linearifo'lius  DC.  Shrubby,  much  branched,  forming  a 
bushy  plant.  Leaves  an  inch  or  less  long,  sometimes  in  clusters,  viscid, 
<nit I  covered  with  resinous  dots.  Heads  solitary  at  the  ends  of  the 
numerous  branchlets,  an  inch  or  more  in  diameter,  with  the  ray 
flowers  irregularly  placed,  so  that  the  head  has  an  untidy  appear- 
ance ;  the  bracts  of  the  involucre  are  also  less  regular  than  in  other 
species.  Akenes  silvery-hairy,  with  white  pappus  that  falls  readily. 
On  dry  hills  in  the  Coast  Mountains. 

/>.  A.  ericoi'des  Hook.  &  Arn.  Shrubby,  much  branched,  with  loir, 
spreading  branches.  Heads  small,  numerous,  with  few  yellow  flowers 
and  but  few  rays.  Leaves  very  numerous,  small,  terete,  closely  clus- 
tered into  small,  somewhat  fan-shaped  bunches,  which  rather  densely  clothe 


170  KEY   AND   FLORA 

the  stem.     This  is  common  on  sand-hills  along1  the  coast.     (There  are 
many  other  species  quite  dissimilar  in  general  appearance.) 

VI.    BIGELO'VIA,  Rabbit-brush 

Herbs  or  shrubs  with  numerous  small  heads  of  yellow 
flowers,  without  rays.  Involucres  narrow,  with  bracts 
arranged  one  above  the  other  in  rows  not  always  distinct, 
without  green  tips.  Akenes  narrow,  usually  nerved.  Pappus 
of  almost  equal  bristles.  The  heads  are  generally  in  close  com- 
pound cymes,  terminating  the  stems. 

B.  arbores'cens  Gray.  Shrubby,  several  feet  high,  with  many  erect 
branches  from  a  woody  stem.  Leaves  linear,  almost  thread-like, 
thickly  clothing  the  stems,  covered  with  resinous  dots.  On  dry  hills 
of  the  Coast  Mountains,  rarely  in  the  Sierra  Nevada  Mountains. 

VH.    SOLIDA'GO,  Golden-rod 

Perennial  herbs  with  erect  stems  and  small  heads  numerous 
in  panicles.  Bracts  of  the  narrow  involucre  not  spreading, 
in  several  rows,  the  outer  ones  regularly  diminishing.  Outer 
/lowers  with  small  rays.  Pappus  in  one  row,  dull  white,  rough 
and  capillary. 

a.  S.  Calif  or'nica  Nutt.     Stems  and  leaves  hoary  and  rough  to  the 
touch,  covered  with  a  fine,  close  pubescence.     Stems  from  1    to   3  ft. 
tall,  terminated  by  the  numerous  heads  of  pale-yellow  flowers  in  a 
close  panicle,  sometimes  pyramidal  and  more  branched.    This  grows 
on  dry  ground,  throughout  California. 

b.  S.  spathula'ta  DC.     Stems  and  leaves  glutinous  (sticking  to  the 
paper  when  pressed),  dark-green.     Stems  1-2  ft.  tall,  terminated  by 
a  spike-like  panicle  of  rather  few  heads,  which  are  larger  than  those 
of  the  other  species.     Lower  leaves  spatulate,  rounded  at  the  apex  and 
serrate,  2-4  in.  long.     This  grows  near  the  coast. 

c.  S.   elonga'ta  Nutt.     Stems   leafy,    with    thin,    Lanceolate,    serrate 
leaves,  2-3  in.  long.     Heads  small,  in  more  open  panicles  than  the 
two  preceding.     Involucre  with  linear  bracts.     This  is  widely  dis- 
tributed, growing  along  streams  and  in  gulches. 

Vm.    AS'TER 

Perennial  herbs  with  solitary  or  clustered  heads  of  flowers 
with  rays  which  are  never  yellow.  The  bracts  of  the  involucre 


DICOTYLEDONOUS   PLANTS  171 

are  in  several  rows,  and  have  green  and  often  leafy  tips. 
Akenes  compressed,  4  or  5  nerved.  Pappus  dull  white  or 
tawny,  of  numerous  rough,  capillary  bristles,  in  a  single  row. 
The  disk  flowers  are  yellow,  often  turning  purple,  and  the  rays 
are  white,  blue,  pink,  or  purplish. 

a.  A.  raduli'nus  Gray.     Stem  simple  below,  from  a  few  inches 
to  1  or  2  ft.  high,  leafy,  branching  above  to  an  open  corymb  of  medium- 
sized  heads.     Leaves  diminishing  towards  the  top,  stiff  and  rough, 
oblong  or  broadly  spatulate,  sharply  serrate  near  the  top,  tapering 
below.     Bracts   of   the  involucre  stiff,   appressed,  with  green  tips 
often   glandular.       Rays   white,    the    disk    corollas   becoming   reddish. 
Pappus  rigid.     Monterey  County  to  Washington. 

b.  A.  Chamisso'nis  Gray.     Stems  2-5  ft.  high,  leafy  and  branch- 
ing, terminated  by  numerous  medium-sized  heads  in  long  racemes  or  in 
widely  branching  panicles.     Leaves  lanceolate,  2-5  in.  long,  entire  or 
slightly  serrate,  sessile.     Bracts  of  the  involucre  in  several  ranks, 
with  short  and  rounded  tips.     Rays  white,  purple,  or  violet,  20-25, 
nearly  half   an    inch    long.     This    is   the   most  widely  distributed 
species.     It  is  somewhat  variable  in  the  size  and  color  of  the  rays 
and  also  the  inflorescence.     Throughout  California  to  Oregon. 

IX.     ERIG'ERON 

This  is  similar  to  Aster,  but  the  bracts  of  the  involucre  are 
in  a  single  row,  or  if  there  is  more  than  one  the  ranks  are  not 
distinctly  apparent.  The  pappus  is  often  in  two  rows,  and 
the  rays  are  generally  more  numerous  and  narrower. 

a.  E.  glau'cus  Ker.     SEASIDE  DAISY.     Generally,  low,  perennial 
herbs,  growing  in  mats  near  the  seacoast.     Leaves  and  stem  covered 
with  soft,  spreading  hairs.     Leaves  broad,  entire ;  the  upper  ones 
sessile,  the  lowest  narrowed  to  a  margined  petiole.     Heads  an  inch 
or  two  in  diameter,  with  numerous  violet  or  white  rays,  and  the  invo- 
lucres soft-hairy  and  somewhat  viscid.     The  stems  are  terminated 
usually  by  solitary  heads ;  sometimes  there  are  3  or  4  in  a  cluster. 
This  is  common  on  the  coast,  and  in  bloom  throughout  the  year. 

b.  E.  Philadel'phicus  L.     Perennial  herbs,  with  stems  from  1  to 
3  ft.  tall,  hairy.     Root  leaves  spatulate  or  obovate,  those  on  the 
stem  oblong,  sessile  by  a  broad,  clasping  base,  irregularly  toothed. 
Heads   in  a  loose  corymb,   with  numerous   very   narrow  pinkish    rays. 
This  is  common  in  wet  places. 

c.  E.    folio'sus   Nutt.      Perennials,    with   several   stems   from    a 
woody  root,  simple,  very  brittle,  and  leafy  up  to  the  corymb,  with 


172  KEY   AND   FLORA 

a  rough,  grayish  pubescence.  Leaves  narrow,  an  inch  or  two  long, 
entire,  diminishing  upwards.  Heads  with  unequal  bracts  to  the  invo- 
lucre and  about  30  bluish  rays.  Inner  pappus  capillary,  outer  of  a 
few  short  bristles.  Throughout  California.  Extremely  variable. 

d.  E.  Canaden'sis  L.  FLEABANE.  Annual  with  stems  from  1 
to  6  ft.  tall.  Heads  very  small,  numerous  in  a  loosely  and  much- 
branched  panicle.  Leaves  mostly  linear,  numerous.  Rays  white, 
inconspicuous.  This  grows  everywhere  and  is  a  common  weed. 

X.    BAC'CHARIS 

Dioecious  shrubs  having  numerous  heads  without  rays  and 
with  the  scales  of  the  involucre  in  several  rows.  Pappus 
capillary  in  one  row,  very  abundant  on  the  female  flowers. 

a.  B.    pilula'ris   DC.     Stems  much  branched,  erect,  several  feet 
high,  in  bunches  often  forming  thickets,  or  (on  the  coast  hills)  low  and 
spreading.     Leaves  sessile,  wedge-shaped,  dark-green,  coarsely  toothed. 
Heads  either  solitary  or  two  or  three  in  a  cluster  in  the  leaf  axils, 
very  numerous.     Male  heads  yellowish  white,  the  stamens  conspicu- 
ous, slightly  surpassing  the  involucre.     Female  flowers  noticeable, 
because  of  the  long  snow-white  pappus,  which  is  much  longer  than 
the  involucre.     This  is  very  common  along  the  entire  coast  in  sandy 
soil.     It  blooms  in  autumn  and  is  often  covered  with  small  gall-nuts. 

b.  B.  Douglas'ii  DC.     Shrubby  at  base,  glutinous,  the  herbaceous 
branches  terminated  by  compound  corymbs.     Leaves  lance-shaped, 
acute,  3-nerved.     Scales  of  the  involucre  broader  in  the  male  heads  than 
in  the  female,  hairy  on  the  margin.     Receptacle  conical.     Flowers 
whitish.     Common  from  San  Francisco  southward,  along  streams. 

c.  B.  vimin'ea  DC.     FLOWERING  WILLOW.     Shrubby,  resembling 
a  willow,  with  woody  branches.     Stems  4-20  ft.  tall.     Leaves  lance- 
shaped,  acute  at  both  ends,  entire  or  with  a  few  teeth.     Heads  numer- 
ous in  corymbs  terminating  the  branches.     Scales  of  the  involucre 
very  thin,  with  hairy,  papery  margins.     Receptacle  flat.     This  is 
found  along  streams  from  Monterey  southward. 

Tribe  3.  INULOI'DE^:.  Anthers  with  tails.  Style  branches 
of  perfect  flowers  neither  truncate  nor  tipped  with  an  append- 
age. Ray  flowers  wanting  in  the  Californian  species. 

XI.    PLU'CHEA,  Marsh  Fleabane 

Annual  herbs  growing  in  salt  or  alkaline  marshes,  glan- 
dular, a  foot  or  two  high.  Heads  numerous  in  dense  corymbose 


DICOTYLEDONOUS  PLANTS  173 

cymes.  Bracts  of  the  involucre  jmrplish,  thin  and  dry,  in 
several  ranks.  Most  of  the  flowers  are  fertile,  the  sterile 
ones  in  the  center  are  purplish  or  sometimes  white.  Pappus 
of  fine,  capillary  bristles,  in  a  single  row. 

P.  camphora'ta  DC.  Leaves  oblong-ovate  to  broadly  lance-shaped, 
nearly  sessile,  irregularly  toothed.  The  entire  plant  has  a  heavy, 
aromatic  odor.  In  salt  or  alkaline  marshes. 


XII.    ANAPH'ALIS,  Pearly  Everlasting 

Dioecious,  perennial  herbs,  with  white-woolly  foliage. 
Involucre  of  many  rows  of  snow-white,  papery  scales.  Style 
2-cleft,  only  at  the  apex.  Pappus  a  single  series  of  capillary 
bristles  falling  separately. 

A.  margarita'cea  Benth.  &  Hook.  Stems  1-3  ft.  high,  leafy  up 
to  the  broad  compound  corymb.  Leaves  narrow,  lance-shaped, 
1-nerved,  becoming  green  and  smooth  above.  Scales  of  the  invo- 
lucre pearly  white,  not  longer  than  the  flowers.  Widely  distributed. 


Xm.    GNAPHA'LIUM,  Everlasting,  Cotton-batting  Plant 

Annual  or  perennial  white-woolly  herbs,  with  whitish  or 
yellowish  flowers.  Heads  with  both  staminate  and  pistillate 
flowers,  the  latter  fewer  and  in  the  center.  Involucre  of  several 
ranks  of  papery  or  papery-tipped  scales.  Styles  in  perfect 
flowers,  2-cleft.  Pappus  of  capillary  bristles  in  a  single  row. 

a.  G.  decur'rens  Ives.     Stems  usually  several  from  the  woody  root, 
1-3  ft.  high  and  rather  stout,  glandular  under  the  dense  wool.     Leaves 
lance-shaped,  with  the  blade  extending  down  the  stem.     Heads  many  in 
dense   corymbs  terminating  the   stems.     Involucre   bell-shaped,   of 
many  papery  scales  in  several  ranks.     The  plant  has  a  peculiar  odor, 
something  like  licorice.      It  is  common  and  widely  distributed  along 
the  coast. 

b.  G.  microceph'arum  Nutt.     Perennial  herbs,  with  slender,  erect 
stems  2  ft.  or  more  high,  loosely  branched  above,  white,  with  a  close 
wool.     Leaves    linear,   the   lowest   spatulate.     Involucre  small,   with 
bright,  white,  obtuse  bracts.      The  herbage  is  odorless,  not,  glandular. 

c.  G.  ramosis'simum  Nutt.     Perennial    herbs   with    erect    stems, 
3-6    ft.    high,    viscid,  green,  with  woolly  covering  not   abundant. 
Heads  in  loose  panicles,  small,   often  with  pink  involucres.     Leaves 


174  KEY   AND   FLORA 

lance-shaped,  with  the  blade  extending  down  the  stem.  The  entire 
plant  has  a  pleasant  aromatic  odor.  Common  on  hills  near  the  coast, 
blooming  in  summer. 

There  are  several  species  besides  these  that  are  quite 
common. 

Tribe  4.  AMBRO'SI^:.  Anthers  distinct  or  slightly  united. 
Style  abortive,  truncate.  Corolla  of  female  flowers  rudi- 
mentary or  none.  Staminate  heads  generally  in  a  cluster 
above  the  pistillate  ones.  Receptacle  with  chaffy  scales. 

XIV.    FRANSE'RIA 

Monoecious.  Staminate  heads  in  many-flowered  racemes. 
Scales  of  the  involucre  united  into  a  cup  ;  receptacle  with 
thread-like  scales  among  the  flowers.  Female  flowers  usu- 
ally one  or  few  in  the  leaf  axils,  each  surrounded  with  a  spiny 
involucre.  Akenes  enclosed  in  the  persistent  involucres,  which 
form  burs. 

a.  F.    bipinnatif  ida  Less.     Low  spreading,  perennial  herbs,  with 
grayish  pubescent  stems  and  leaves.     Leaves  twice  or  thrice  pinnately 
divided  into  roundish  divisions.     On  the  coast  from  Washington  to 
San  Diego. 

b.  F.  Chamisso'nis  Less.     Similar  to  the  above,   with  which   it 
seems  to  mix.     The  leaves  are  ovate  or  wedge-shaped,  with  obtuse 
teeth.      These  two  species  grow  on  the  sand  dunes  of  the  coast  and 
are  frequently  associated. 

XV.    XAN'THIUM,  Cocklebur 

Monoecious.  Male  heads  many-flowered,  with  the  scales  of 
the  involucre  distinct  in  one  series  ;  receptacle  cylindrical. 
Female  heads  united  and  enveloping  the  akene,  armed  with 
hooked  spines.  These  are  stout  annual  herbs,  with  an  abun- 
dance of  large  burs  in  the  fall. 

a.  X.  struma'rium  L.     Leaves  broadly  ovate,  cordate,  green  on 
both  sides,  on  long  petioles,  rough,  irregularly  toothed.     Burs  f  in. 
long,  ovate,  tipped  with  two  stout  beaks.      Common,  introduced. 

b.  X.  spino'sum  L.     Stems  much  branched,  very  spiny,  with  long 
triple  yellow  spines  by  the  sides  of  the  leaves.     Leaves  lanceolate, 
white  beneath,   twice  or  thrice   lobed  or   cut,   tapering  into   short 


DICOTYLEDONOUS  PLANTS  175 

petioles.     Burs  flat,  less  prickly  and  with  weaker  prickles  than  the 
preceding,  and  inconspicuous  beaks.     Common,  introduced. 

Tribe  5.  HELIANTHOI'DE^:.  Anthers  without  tails.  Style 
branches  of  perfect  flowers,  truncate  or  tipped  with  an  append- 
age. Bracts  of  the  involucre  not  papery.  Pappus  never 
capillary.  Receptacle  with  chaffy  scales  mixed  among  the 
flowers  or  only  near  those  on  the  outside. 

XVI.    WYE'THIA,  California  Compass  Plants 

Perennial  herbs  with  simple  stems  from  a  stout  rootstock. 
Leaves  alternate,  large,  the  same  on  both  sides,  erect,  the 
edges  pointing  north  and  south.  Heads  usually  solitary,  large, 
with  long  broad,  yellow  rays.  Bracts  of  the  involucre  in  2  or 
3  rows,  the  outer  leaf -like,  the  inner  thinner  and  somewhat 
membranous.  Eeceptacle  flat,  with  the  chaffy  scales  partially 
folded  around  the  akenes.  Pappus  forming  a  cup  on  top  of 
the  akene,  or  of  from  1  to  4  rigid  chaffy  awns.  These  plants 
bloom  early  in  the  flowering  season. 

a.  W.  helenioi'des  Nutt.     Stems  and  leaves  white-woolly  when  young. 
Leaves  all  on  short  petioles,  the  lowest  a  foot  or  two  long,  4-8  in.  wide. 
Heads  large,  4  in.  or  more  in  diameter,  leafy  at  base.    Akenes  pubes- 
cent towards  the  apex.     Pappus  scales  more  or  less  united  into  a 
cup.     In  bloom  early.     Around  San  Francisco  Bay  on  hillsides. 

b.  W.  gla'bra  Gray.     Similar  to  the  preceding,  but  the  whole  plant 
is  smooth  and  somewhat  glutinous,  the  leaves  are  leathery  and  dark-green. 
Akenes  smooth.     In  bloom  in  April  and  May.     In  the  Coast  Moun- 
tains, from  Marin  County  southward. 

c.  W.  angustifolia  Nutt.     Radical  leaves  long-lanceolate,  pointed  at 
both  ends.    Heads  smaller  than  the  two  preceding,  on  long  peduncles, 
leafy  only  at  base.     Bracts  of  the  involucre  numerous,  lanceolate, 
hairy  on  the  margin,  loose  and  leafy.     Pappus  of  1-4  stout  hirsute 
awns,  with  short  intervening  scales.     This  is  in  bloom  the  latest. 
It  is  common  and  widely  distributed. 

d.  W.  amplexicau'lis  Nutt.     Smooth.     Upper  leaves  sessile.     Invo- 
lucre  broad,    bell-shaped,    of   many   loose   scales.      Pappus    irithont 
bristles.     Eastern  Oregon  to  Washington. 

XVH.    BALSAMORRHFZA,  Balsam-root 

Perennial  herbs  with  thick  aromatic  roots  and  large  leaves 
chiefly  from  the  root.  Heads  large,  usually  solitary  and 


176  KEY  AND  FLORA 

terminating  almost  leafless  steins,  containing  many  flowers. 
Involucre  of  many  loose  leaf-like  scales  in  several  ranks. 
Eay  and  disk  flowers  fertile,  yellow.  Pappus  none.  Akene 
of  the  ray  flowers  flattened  parallel  with  the  scales;  those  of  the 
disk  with  4  angles. 

a.  B.  sagitta'ta  Nutt.     Densely  covered  with    white  wool.     Leaves 
entire,  heart-shaped  or  arrow-shaped,  4-8  in.  long,  on  long  petioles. 
Scapes   a  foot  or  two   high.     Rays  yellow,  1-2  in.  long.     In   the 
Sierra  Nevada  Mountains  to  British  Columbia,  blooming  in  early 
spring. 

b.  B.  deltoi'dea  Nutt.      Green  and  almost  smooth.     Leaves  broadly 
heart-shaped  to  V-shaped,  irregularly  serrate  or  entire,  4-10  in.  long. 
Scapes  with  small  lanceolate  or  cordate  leaves  bearing  1-3  heads. 
Rays  an  inch  or  more  long.     Southern  California  to  British  Colum- 
bia, blooming  in  early  spring. 

XVIII.    HELIAN'THUS,  Sunflower 

Annual  or  perennial  herbs  with  the  lowest  leaves  opposite, 
the  upper  alternate,  all  simple.  Heads  large,  with  conspicu- 
ous yellow  rays.  Bracts  of  the  involucre  in  several  series, 
green,  but  not  leaf-like.  Receptacle  flat,  with  the  chaffy 
scales  numerous.  Akenes  slightly  flattened,  4-sided.  Pap- 
pus of  2  marginal  scales  that  fall  soon,  and  more  persistent 
minute  bristles  between. 

H.  Califor'nicus  DC.  Stems  tall,  2-5  ft.  high,  branching  above. 
Leaves  long,  lanceolate,  or  broader  at  base.  Bracts  of  the  involucre 
narrow,  linear-lanceolate,  tapering  to  a  long-spreading  point.  Recep- 
tacle convex,  with  the  chaffy  scales  blunt.  Akenes  flat,  with  a 
smooth  pappus  of  2  or  3  chaffy  scales.  This  grows  along  streams. 
The  flowers  are  quite  numerous  on  the  branches  at  the  top  of  the 
stem.  Common  from  around  San  Francisco  southward.  Summer 
and  fall. 

XIX.    ENCE'LIA 

Perennial,  shrubby  at  base,  branching.  Leaves  opposite  or 
alternate,  generally  simple.  Heads  containing  many  flowers  ; 
disk  flowers  perfect  ;  ray  flowers  generally  present  and 
neutral.  Involucre  bell-shaped  with  the  scales  in  several 
rows  one  above  the  other.  Akenes  flatj  with  a  thin  edge  but 


DICOTYLEDONOUS   PLANTS  177 

without  wings,  obovate,  2-toothed  at  summit  or  notched,   with 
long  hairs  or  without.     Pappus  none  or  a  pair  of  bristles. 

E.  Califor'nica  Nutt.  Gray  pubescent  at  first  but  becoming 
smoother  and  greener.  Leaves  alternate,  ovate  to  lanceolate,  1-2 
in.  long.  Involucre  covered  with  white  hairs.  Rays  an  inch  long, 
yellow. 

XX.    LEPTOS'YNE 

Smooth  succulent  herbs,  with  leaves  twice  or  thrice  pin- 
nately  parted  into  narrow,  linear  lobes.  Heads  on  long 
peduncles,  with  a  double  involucre,  the  outer  of  5-8  narrow, 
leaf-like  scales,  the  inner  of  8-12  thinner  and  broader  erect 
scales.  Rays  yellow,  conspicuous,  oblong,  3-toothed,  10-nerved. 
Keceptacle  nearly  flat,  with  thin  papery  chaff  that  falls  with 
the  fruit.  Corollas  of  the  disk  flowers  with  a  slender  tube 
having  a  ring  around  the  summit  below  the  funnel-form 
border.  Akenes  flat,  more  or  less  margined  with  a  wing. 
Pappus  none,  or  a  minute  cup. 

a.  L.  Douglas'ii  DC.    Annual.     Stems  leafy  only  at  base.     Heads 
on  long,  naked  peduncles.     Rings  on  the  corolla  tube  hairy.     Common 
in  southern  California. 

b.  L.   Still'mani  Gray.     Stems  leafy  below.     Involucre  hairy  at 
base.     Ring  on  the  corolla  tube  smooth.     This  is  the  commonest  species. 

c.  L.  marit'ima  and  L.  gigante'a  are  shrubby,  perennial  species 
with  thick  fleshy  stems.     The  former  grows  near  San  Diego  on  the 
coast ;  and  the  latter,  which  has  a  strong  odor  of  turpentine,  near 
the  coast  in  Ventura  and  San  Luis  Obispo  Counties,  and  on  the 
islands  off  the  coast  of  Santa  Barbara. 


XXI.    BFDENS,  Bur  Marigold 

Annual  herbs,  usually  growing  near  water.  Leaves  opposite. 
Involucre  double,  as  in  Leptosyne.  Receptacle  flat  or  convex, 
the  thin,  narrow,  chaffy  scales  falling  with  the  fruit.  Akenes 
with  a  pappus  of  2-4  awns,  barbed  downwards.  The  species 
are  somewhat  uncertain. 

XXH.    MA'DIA,  Tarweed 

Annuals  with  glandular,  aromatic  foliage  and  flowers  that 
wilt  during  the  heat  of  the  day.  Bracts  of  the  involucre  in 


178  KEY  AND  FLORA 

one  series,  boat-shaped,  and  embracing  the  black  or  brown 
flattened  akenes.  Receptacle  without  chaffy  scales  in  the 
center,  but  with  one  or  two  rows  between  the  disk  and  the 
ray.  Ray  flowers  and  usually  disk  flowers  without  pappus. 
Rays  yellow,  sometimes  with  a  brown  spot  at  base. 

a.  M.  eregans  Don.     Stems  branching.     Heads  in  loose  panicles 
an  inch  in  diameter,  with  conspicuous  yellow  rays,  often  with  a  brotcn 
spot  at  base.     Foliage  lemon-scented.     Widely  distributed. 

b.  M.    sati'va    Molina.       Stems    simple    or    branching.      Heads 
usually  densely  clustered,  with  inconspicuous  yellow  rays.     The  bracts 
enclosing  the  akenes  persist  around  the  akenes  and  adhere  to  other 
substances  by  means  of  their  viscidity,  thus  accomplishing  the  dis- 
tribution of  the  seed.     Widely  distributed. 


XXHI.    HEMIZO'NIA,  Tarweed 

This  is  similar  to  Madia,  the  chief  difference  being  the 
bracts  enclosing  the  akenes,  which  in  Madia  almost  entirely 
surround  the  individual  akenes,  while  in  Hemizonia  they  only 
half  enclose  them.  ("  Hemizonia  "  means  half  zone.)  The 
disk  flowers  generally  have  pappus  and  the  rays  are  either 
yellow  or  white.  Anthers  brown. 

a.  H.  luzulaefo'lia  DC.     Annual,  widely  branching.     Lower  leaves 
long,  linear,  silvery,  with  shining  white  hairs,  the  upper  leaves  very  glan- 
dular.    Heads  numerous,  with  white  or  yellow  3-lobed  rays  less  than 
j?  in.  long,  the  dark-brown  anthers  conspicuous.     This  is  one  of  the 
commonest  Tarweeds,  blooming  in  summer  and  fall. 

b.  H.  pun'gens  (Centroma'dia) .     Stems  much  branched,  hirsute. 
Lower  leaves  twice  pinnatifid,  with  short  spiny  lobes,  those  on  the 
branchlets  entire,  crowded,  spine-tipped.     Bracts  of  the  involucre  spiny, 
and  also  the  narrow  chaff  of  the  receptacle.     Rays  about  as  long  as  the 
disk,  2  or  3  toothed.     Pappus  none.     This  is  common,  blooming  in 
summer  and  fall. 

c.  H.  multiglandulo'sa  Gray  (Calycade'nia) .     Annuals,  with  erect 
stems   and   branches ;  covered,  especially   above,  with   black   tack- 
shaped   glands ;    lemon-scented.      Leaves   narrowly   linear.     Heads 
crowded  in  the   axils  of  the   upper  leaves    or    sometimes  solitary. 
Flowers   white    or   tinged   with    rose-color,  the  rays  1-7,   broad,   deeply 
3-lobed.     Receptacle  flat,  with  chaffy   scales  only  between  the  ray 
and  the   disk    flowers.     Common    in   California.     The   species   are 
very  numerous  and  difficult. 


DICOTYLEDONOUS   PLANTS  179 


XXIV.     LAY'IA,  Tidy-tips  (BLEPHARIPAP'PUS) 

Annual  herbs  with  alternate  leaves.  Heads  many-flowered, 
with  wedge-shaped,  3-toothed  rays.  Bracts  of  the  involucre 
in  one  series,  with  papery  margins  and  pointed  tips,  com- 
pletely enclosing  the  ray  akenes.  Receptacle  flat,  with  a  row 
of  chaffy  scales  between  the  ray  and  the  disk,  or  chaffy  through- 
out. Ray  akenes  linear,  often  purplish,  narrowed  to  the  base, 
flat  on  top,  without  pappus.  They  bloom  in  the  spring. 

a.  L.  glandulo'sa  Hook.  &  Arn.     Loosely  branching,  about  a  foot 
high,  hairy,  and  sprinkled  above  with  stipitate,  dark-colored  glands. 
Pappus  of  disk  flowers,  of  10-20  stout  bristles,  that  are  densely  white- 
woolly  below  the  middle.     Heads  medium-sized,  with    8-13,   3-lobed, 
conspicuous    white    or    rose-purple    rays   and    yellow    disk.       Widely 
distributed. 

b.  L.  platyglos'sa  Gray.     TIDY-TIPS.     Loosely  branching  or  often 
simple-stemmed,    hairy,    and    glandular.       Lower    leaves    pinriately 
lobed,  with  narrow  divisions.     Heads  with  large  rays,  bright  yellow, 
edged  with  white.     Pappus  of  15-25  stout,  rough  bristles,  that  are  not 
woolly.    Ray  akenes  smooth,  those  of  the  disk  silky-hairy.    Through- 
out  California.       (There   are   several   other   species   not  so   easily 
distinguished.) 

Tribe  6.  HELENIOI'DE^E.  Similar  to  Helianthoidece,  but 
without  chaffy  scales  on  the  receptacle. 

XXV.    BAE'RIA,  Golden  Fields  (LASTHENIA) 

Low  annuals  with  opposite  leaves,  entire  or  irregularly  pin- 
natifid  into  linear  lobes.  Heads  small,  on  slender  peduncles, 
terminating  the  branches  or  stems.  Involucre  formed  of  a 
single  series  of  flat,  oblong  scales.  Kays  entire  or  3-toothed, 
oval  or  oblong.  Receptacle  conical,  rough,  with  projecting 
points  that  bear  the  akenes.  Akenes  angled  or  nerved.  Pap- 
pus either  scales  or  bristles,  or  none.  These  little  plants 
cover  the  ground  for  acres,  and  look  like  a  golden  carpet 
spread  over  the  earth.  Some  species  have  a  sweet,  rather 
heavy  perfume. 

B.  gra'cilis  Gray.  SUNSHINE.  This  is  the  most  widely  spread  spe- 
cies, but  it  is  not  easily  distinguished  from  the  others.  Fragrant. 


180  KEY   AND   FLORA 


XXVI.    BLENNOSPER'MA 

Annuals,  low,  slender,  much  branched,  smooth.  Leaves 
pinnately  parted  into  many,  narrow,  linear  divisions.  Heads 
small,  terminating  the  branchlets.  Flowers  many,  light 
yellow.  Involucre  with  bracts  in  a  single  series,  generally 
tipped  with  dark  red.  Receptacle  fiat.  Ray  flowers  pistillate, 
without  pappus  ;  disk  flowers  sterile,  except  the  row  next  to  the 
ray  flowers.  Akenes  covered  with  white  dots  which  become  jelly- 
like  when  wet. 

B.  Califor'nicum  T.  &  G.  This  is  the  only  species.  It  grows  in 
wet  places  in  early  spring  and  often  covers  the  ground  for  miles 
along  highways. 

XXVII.    ERIOPHYI/LUM 

Shrubs  or  herbs  with  entire  or  divided  leaves  clothed  with 
cottony  wool,  especially  on  the  under  surface.  Flowers  yellow. 
Bracts  of  the  involucre  lance-shaped,  united  at  base.  Pappus 
of  membranaceous  scales. 

a.  E.  staechadifo'lium  Lag.     LIZARD-LEAF.     Shrubby,  with  many 
stems  rising  from  a  woody  base,  terminated  by  loose  cymes  of  rather 
small  heads.     Leaves  cut  into   linear,  pinnate   divisions   somewhat 
resembling  a  lizard  in  outline,  green  above,  white  below.     Common 
in  the  Coast  Mountains. 

b.  E.   confertiflo'rum  Gray.     Similar   to  the  above,  but  smaller, 
with  leaves  reduced  and  scattered,  white  on  both  sides.     Heads  almost 
destitute  of  rays  in  a  dense  corymb.     Extending  to  the  Sierras,  as  well 
as  in  the  Coast  Mountains. 

c.  E.    caespito'sum   Dougl.     Perennial   herbs,    with   many    stems 
from  the  root.     Heads  nearly  an  inch  in  diameter,  with  conspicuous 
rays,  solitary  or  few,  on  long  peduncles.     This  is  extremely  variable 
and  widely  distributed. 

XXVIH.    MONOLO'PIA 

Annual  herbs  with  woolly  pubescence  and  sessile  leaves 
alternate  above,  sometimes  opposite  below.  Heads  large, 
terminating  the  stems  ;  scales  of  the  involucre  united  into  a 
toothed  cup.  Receptacle  conical,  papillose.  Pappus  none. 
Flowers  yellow,  with  conspicuous  rays. 


DICOTYLEDONOUS   PLANTS  181 

M.  ma'jor  DC.  Ray  corollas,  with  a  broad  3  or  4  toothed  or 
lobed  ray,  and  bearing  on  the  opposite  side  of  the  style  a  roundish, 
toothed  appendage.  Leaves  simple,  partly  clasping.  Pleads  nearly 
2  in.  in  diameter,  very  showy.  Throughout  western  California,  in 
low  ground. 

XXIX.    CHJENACTIS 

Herbs  with  pinnately  compound  leaves,  more  or  less  white- 
woolly,  and  heads  of  yellow,  white,  or  flesh-colored  flowers 
without  rays ;  the  outer  corollas  often  have  an  enlarged 
border  simulating  a  ray.  Involucre  with  green,  linear,  erect 
bracts,  generally  in  a  single  row.  Receptacle  flat.  Pappus 
of  chaffy  scales.  Akenes  slender.  The  heads  are  solitary, 
or  in  loose  clusters  on  peduncles.  The  species  are  not  easily 
distinguished. 

XXX.    HELE'NIUM,   Sneezeweed 

Annual  or  perennial  herbs  with  alternate  leaves,  and  heads 
on  peduncles  terminating  the  branchlets.  Bracts  of  the 
involucre  in  2  series,  the  external  scales  narrow,  leaf-like, 
spreading,  and  at  length  reflexed,  the  internal  scales  few  and 
chaffy.  Receptacle  globular.  Pappus  of  5-12  thin,  chaffy 
scales.  Ray  flowers  yellow,  disk  flowers  often  purplish. 

a.  H.  puber'ulum  DC.     Widely  branched,  the  stems  winged  with 
the  decurrent  leaves.     Disk  forming  a  round  ball,  ray  flowers  incon- 
spicuous.    This  is  common  in  wet  places. 

b.  H.    Bolan'deri   Gray.      Perennial,   with   sterns   a  foot   or   two 
high.     Heads   on   long,   naked   peduncles  which  are  thickened  at 
top.      Leaves   obovate    or   lanceolate.      Heads   large,  with   wedge- 
shaped  rays  an  inch  long;    disk   an   inch   across.     From  northern 
California  to  Washington. 

c.  H.  Bigelo'vii  Gray.     Stems  tall  and  simple.     Leaves  lanceolate 
to  oblong  or  linear,  entire.     Heads  on  long,  slender  peduncles,  with 
rays    half   an  inch    long   and  disk   as  broad,  somewhat  depressed. 
Common  in  wet  places  in  the  Sierra  Nevada  Mountains  of  California. 

Tribe  7.  ANTHEMOI'DE^C.  Similar  to  Helianthoidece,  but 
the  involucre  consists  of  papery  bracts  in  regular  rows,  the 
pappus  is  a  short  crown  or  wanting,  and  the  receptacle  rarely 
has  chaffy  scales  mixed  with  the  flowers. 


182  KEY   AND   FLORA 


XXXI.    AN'THEMIS,  Dog  Fennel 

Herbs  with  pinnately  dissected  leaves  and  numerous  heads, 
terminating  the  branchlets.  Scales  of  the  involucre  in  several 
series,  one  above  the  other.  Receptacle  convex  or  conical, 
having  chaffy  scales  among  the  flowers.  Ray  flowers  white, 
those  of  the  disk  yellow.  Pappus  none.  Akenes  ribbed. 

A.  Cot'ula  L.  WHITEWEED,  MAYWEED.  This  is  a  common  intro- 
duced weed,  and  blooms  in  summer  and  fall.  It  has  a  strong,  acrid 
taste  disagreeable  to  animals. 

XXXII.    ACHILLE'A,  Yarrow,  Milfoil 

Perennial  herbs,  strong-scented,  with  pinnately  dissected 
leaves.  Stems  usually  simple,  terminated  by  dense  corymbs  of 
small  heads  of  white  or  pinkish  flowers.  Involucres  with 
small  scales  in  several  rows.  Pappus  none,  akenes  flattened, 
margined.  Bracts  of  the  receptacle  thin  and  transparent. 

A.  millefo'lium  L.  This  is  common  and  widely  distributed.  The 
leaves  are  disposed  to  form  rosettes  at  the  base  of  the  stem,  and  are 
delicate  and  fern-like. 


XXXIII.    MATRICA'RIA,  Chamomile 

Erect  simple  or  branching  herbs,  with  pinnately  dissected 
leaves.  Heads  terminating  the  branches,  on  short  peduncles. 
Bracts  of  the  involucre  in  several  series.  Disk  greenish 
yellow,  conical.  Rays  white  when  present.  Pappus  in  a  crown 
or  wanting. 

M.  discoi'dea  DC.  MANZANILLA.  Annual,  erect,  branching. 
Heads  with  a  high  conical  disk  and  no  rays.  Involucre  with  white, 
papery  margins  to  the  broadly  ovate  scales.  Akenes  with  a  crown- 
like  margin  in  place  of  pappus.  This  plant  has  the  odor  of  ripe 
apples.  Widely  distributed. 

XXXIV.    ARTEMISIA,  Wormwood,  Sagebrush 

Herbs  or  shrubs  with  bitter  taste  and  alternate  leaves. 
Heads  greenish,  small,  without  rays,  numerous  in  racemes  or 
panicles.  Scales  of  the  involucre  dry,  with  papery  margins. 


DICOTYLEDONOUS   PLANTS  183 

Receptacle  naked  or  hairy.  Akenes  obovate,  with  a  small  disk 
at  top,  but  without  pappus.  These  have  inconspicuous  flowers, 
often  an  aromatic  odor,  and  they  bloom  in  the  fall. 

a.  A.  vulga'ris  var.  Californica  Besser.  MUGWORT.  Stems  simple 
and  tall.  Upper  leaves  toothed  or  entire,  lower  3-5-parted,  green  on 
the  upper  surface,  white-woolly  below.  This  grows  in  gulches  and 
along  streams,  and  is  widely  distributed. 

6.  A.  Calif or'nica  Less.  FLEABANE.  Shrubby,  with  many  branches 
from  a  woody  base,  3-4  ft.  high,  forming  a  clump.  Entire  plant 
white-pubescent.  Leaves  pinnately  divided  into  thread-like  divisions. 
This  grows  on  dry  hills  and  is  pleasantly  aromatic.  Common  from 
San  Francisco  southward. 

XXXV.    COT'ULA,  Brass-buttons 

Small  introduced  annual  herbs,  having  heads  without  rays. 
Bracts  of  the  involucre  nearly  equal,  papery  on  the  margins, 
in  2  ranks.  Receptacle  flat,  naked,  papillose.  Akenes  flat- 
tened, with  spongy  margins.  Pappus  none.  Flowers  yellow. 

a.  C.  coronopifo'lia  L.     Smooth,  with  creeping  stems  and  rather 
fleshy  leaves,  which  are  lanceolate,  irregularly  pinnatifid,  toothed  or 
entire,  with  broad,  clasping  base.     Heads  &  in.  in  diameter,  flat  on 
top,  the  bright-yellow  disk  flowers  very  numerous.     This  grows  in  wet 
places,  and  is  very  common  near  the  coast. 

b.  C.  Austra'lis  L.     Smaller  than  the  preceding,  hairy.     Leaves 
twice  pinnately  parted  into  linear  divisions.     Heads  very  small,  with 
flowers  greenish.     This  grows  along  the  streets  and  in  waste  places. 

Tribe  8.  SENECIONID'E^:.  Similar  to  Helianthoidece,  but 
the  pappus  is  abundant  and  capillary,  and  the  receptacle  is 
without  chaffy  scales. 

XXXVI.     AR'NICA 

Perennial  herbs  with  creeping  rootstocks,  and  simple  stems 
bearing  a  few  rather  large  heads  of  yellow  flowers  on  long 
peduncles  and  usually  a  few  opposite,  entire  or  toothed  leaves. 
Involucre  bell-shaped,  of  linear  or  lance-shaped  equal  scales  in 
one  or  two  series,  Kays  elongated  or  sometimes  wanting. 
Pappus  a  single  row  of  stiff,  bearded,  capillary  bristles. 
Akenes  linear,  5-angled,  or  ribbed. 


184  KEY   AND   FLORA 

a.  A.  discoi'dea  Benth.     Heads  without  rays  in  a  bractless  panicle. 
Involucre  hairy  and  glandular.     Leaves  ovate  or  oblong,  irregularly 
toothed,  the  upper  sessile  and  often  alternate.     Akenes  becoming 
smooth,  not  glandular.     In  the  Coast  Mountains. 

b.  A.  cordifo'lia  Hook.     Heads  with  conspicuous  rays,  usually  about 
£  in.  long   (rarely  rayless).     Leaves  opposite,    2  pairs  on   the  stem; 
root  leaves  roundish  and  deeply  cordate,  coarsely  toothed.     In  the 
Sierra  Nevada  Mountains. 

c.  A.  folio'sa  Nutt.     Perennial,   from   rootstocks.     Stems  erect, 
leafy,  clothed  with  white  wool.     Leaves  lanceolate,  with  small  blunt 
teeth  on  the  margin  and  with  5  parallel    longitudinal  nerves.     Heads 
rather  small,  in  corymbs,  on  short  peduncles.     Rays  short,  yellow. 
Common  in  the  Sierra  Nevada  Mountains,  north  to  Oregon,  bloom- 
ing in  summer. 

XXXVH.    SENE'CIO,  Groundsel 

Herbs  or  shrubs  with  alternate  leaves  and  heads  of  yellow 
flowers  either  solitary  or  in  corymbs.  Bracts  of  the  involucre 
in  a  single  series,  somewhat  united,  often  with  a  few  loose 
bracts  at  the  base.  Akenes  slender,  with  fine  and  soft  copious 
pappus. 

a.  S.  vulga'ris  L.     OLD  MAN  OF  SPRING.     Annual,  from  a  few 
inches  to   a   foot   high.     Leaves  rather   thick,  pinnately  cut   into 
toothed   lobes.     Scales    at  the  base  of  the  involucre  tipped  with 
black.     Heads  small,  rayless.     This  is  common  in  fields  and  along 
roads.     An  introduced  weed. 

b.  S.  Douglas'ii  DC.     Perennial,  sometimes  shrubby,  leafy  to  the  top, 
usually  white,  with  cottony  wool   more   or  less  persisting.     Leaves 
linear,  entire,  acute,  or  pinnately  parted  into  linear   lobes.-    Heads  in 
corymbs  at  the  ends  of  the  branches,  about  an  inch  in  diameter. 
Involucre  with   a   few  loose  scales  at  the  base.     Rays   elongated. 
Widely  distributed. 

c.  S.  aronicoi'des  DC.     Stems   stout,  erect,    leafy   at   base,  witli 
leaves  irregularly  and   coarsely  toothed,  3-6   in.   long.     Heads    rather 
small,  in  compound  cymes  terminating  the  stems,  without  rays  or 
with  only  one  or  two.     Bracts  of  the  involucre  without  black  tips. 
Common  throughout  California  in  low  grounds. 

d.  S.  euryceph'alus  Ton.  &  Gray.     Stems  stout,  erect,  leafy,  some- 
what white-woolly  when  young,  becoming  smoother  with  age.    Leaves 
unequally  pinnately  parted,   with    wedge-shaped,   acutely  incised   lobes. 
Heads  many  in  an  ample  corymb,  with  10-12  long  and  showy  rays. 

e.  S.  Califor'nicus  DC.     Annual,  a  foot  or  two  high,  with  smooth, 
slender  stems.    Leaves  linear  to  oblong ;  those  on  the  stem  clasping  at  base ; 


DICOTYLEDONOUS   PLANTS  185 

those  near  the  base  toothed  or  loberl.  Heads  in  corymbs,  with  rays  half 
an  inch  long.  Common  in  southern  California,  blooming  in  spring. 
/.  S.  triangula'ris  Hook.  Stems  simple,  smooth,  leafy,  2-5  ft. 
high.  Leaves  triangular,  sharply  toothed,  pointed  at  top.  Heads  many, 
in  corymbs  terminating  the  stem.  Involucre  bell-shaped,  with  a 
few  loose,  narrow  bracts  at  base.  Rays  6-12,  half  an  inch  long. 
In  the  Sierra  Nevada  Mountains  to  Washington.  Summer. 

Tribe  9.  CYNAROI'DEJE.  Anthers  either  with  tails  or 
arrow-shaped.  Style  branches  without  tips  or  appendages, 
often  united  near  the  apex.  Corollas  all  tubular,  with  long, 
narrow,  linear  divisions.  Receptacle  densely  bristly. 

XXXVIII.    CIR'SIUM  (CNI'CUS),  (CAR'DUUS)  Thistle 

Stout  herbs,  usually  biennial,  with  alternate  prickly  leaves 
and  large  or  medium-sized  heads  of  purple,  red,  white,  or 
yellowish  flowers.  Scales  of  the  involucre  bristle-tipped, 
arranged  in  many  series,  the  lower  successively  shorter. 
Receptacle  flat,  densely  clothed  with  bristles.  Akenes  smooth, 
obovate  or  oblong.  Pappus  of  numerous,  long,  plumose  bristles 
that  are  deciduous,  united  in  a  ring.  The  style  is  usually 
thickened  by  a  knee-like  swelling  immediately  below  the  stig- 
matic  portion,  which  consists  of  two  slender  divisions  united 
nearly  or  quite  to  the  top.  The  species  are  not  easily 
determined. 

XXXIX.    SIL'YBUM,  Milk  Thistle 

Stout  annuals,  nearly  smooth,  with  large  root  leaves 
blotched  with  white,  and  prickly  on  the  margins.  Heads 
many-flowered  and  often  solitary.  Involucre  with  leaf -like 
closely  appressed  bracts,  tipped  with  stout  spines.  Flowers 
magenta-purple.  Pappus  of  stiff,  chaffy  bristles  in  several 
rows,  not  spiny. 

S.  Maria'num  Gaertn.  This  has  been  introduced  from  the  Medi- 
terranean region,  and  is  spreading  more  and  more. 

XL.    CENTAURE'A,  Star  Thistle 

Herbs  with  small  heads  of  yellow,  rose-color,  or  blue  flowers. 
Involucre  globular,  the  scales  spine-tipped  or  papery  at 


186  KEY  AND   FLORA 

the  apex,  generally  contracted  under  the  flowers.  Receptacle 
very  bristly.  Akenes  compressed,  with  pappus  of  numerous 
chaffy  bristles  that  fall  separately.  The  outer  flowers  are 
often  funnel-shaped,  with  broad  conspicuous  divisions  simu- 
lating a  ray  flower.  All  the  species  are  introduced  weeds 
from  Europe. 

a.  C.  Meliten'sis  L.    TOCALOTE.    Annual,  with  spreading  branches. 
Radical  leaves  pinnatifid,  with  rather  broad  lobes,  the  stem  leaves 
barely  toothed,  decurrent.      Corollas  yellow,  inconspicuous.     Scales  of 
the  involucre   spine-tipped,  and   with  a   few  prickles  at  the  base. 
Common  in  fields  and  waste  places. 

b.  C.    solstitia'lis   L.      Annual,    much   branched.      Stem   leaves 
linear.     Flowers  conspicuous  yellow.     Outer  bracts  of  the  involucre 
with  3-5  small  prickles,  palmately  spreading  ;  middle  bracts  with  a 
stout  spine  besides.    This  is  less  common  than  the  preceding. 


INDEX 


Abies,  16. 
Abronia,  52. 
Acacia,  95. 
Acer,  102. 
Achillea,  182. 
Achlys,  63. 
Aconite,  61. 
Aconitum,  61. 
Actaea,  61. 
Adder's  Tongue,  29. 
Adenostoina,  84. 
^Esculus,  102. 
Agave,  37. 
Alabaster  Tulip,  30. 
Alder,  43. 
Alder  Family,  42. 
Alfalfa,  92. 
Alfilerilla,  90. 
Allium,  24. 
Alnus,  43. 
Alum  Root,  77. 
Amarantacese,  61. 
Amaranth  Family,  51. 
Amarantus,  51. 
Amaryllidacese,  36. 
Ambrosise,  162,  174. 
Amelanchier,  87.. 
American  Aloe,  37. 
Amole,  33. 
Amsinckia,  137. 
Amygdalese,  80. 
Anacardiaceae,  101. 
Anagallis,  126. 


Anaphalis,  173. 
Anemone,  59. 
Anemopsis,  40. 
Angiosperms,  20. 
Anthemis,  182. 
Anthemoidese,  163,  181, 
Apetalous  Plants,  39. 
Aphyllon,  153. 
Aplopappus,  169. 
Apocynacese,  130. 
Apocynum,  130. 
Apple,  88. 
Aquilegia,  60. 
Arabia,  71. 
Aracese,  23. 
Aralia,  117. 
Araliacese,  116. 
Arbor-vitse,  14. 
Arbutus,  121. 
Arctostaphylos,  121. 
Arenaria,  56. 
Argemone,  65. 
Aristolochia,  47. 
Aristolochiaceae,  46. 
Armeria,  127. 
Arnica,  183. 
Artemisia,  182. 
Arum  Family,  23. 
Asarum,  46. 
Asclepiadacese,  129. 
Asclepias,  129. 
Ash,  128. 
Ash  Family,  127. 


187 


190 


KEY  AND  FLORA 


Clover,  91. 
Cnicus,  185. 
Cocklebur,  174. 
Coffee  Berry,  103. 
Collinsia,  147. 
Collomia,  131. 
Columbine,  60. 
Column  Cactus,  116. 
Composite,  161. 
Composite  Family,  161. 
Coniferse,  13. 
Convolvulacege,  132. 
Convolvulus,  132. 
Cornaceae,  119. 
Corn  Spurry,  57. 
Cornus,  119. 
Corylus,  46. 

Cotton-batting  Plant,  173. 
Cottonwood,  42. 
Cotula,  183. 
Cotyledon,  74. 
Cow  Parsnip,  118. 
Crane's  Bill,  95. 
Crassulacese,  74. 
Cratsegus,  88. 
Cream  Cups,  65. 
Creeping  Violet,  109. 
Cress,  70. 
CrucifersB,  67. 
Cucurbitaceae,  158. 
Cupressus,  13. 
Cupuliferae,  44. 
Curly  Dock,  48. 
Currant,  78. 
Cuscuta,  133. 
Cyclamen,  125. 
Cynaroideee,  164,  185. 
Cynoglossum,  138. 
Cyperacese,  22. 
Cypress,  13. 
Cypripedium,  39. 


Daffodil,  36. 
Dandelion,  166. 
Datura,  145. 
Daucus,  119. 
Death  Camass,  34. 
Deer's  Foot,  63. 
Delphinium,  61. 
Dendromecon,  64. 
Dentaria,  71. 
Devil's  Club,  117. 
Dicentra,  67. 
Dichelostemma,  26. 
Dicotyledonous  Plants,  39. 
Digger  Pine,  20. 
Diogenes'  Lantern,  30. 
Diplacus,  152. 
Disporum,  34. 
Dock,  48. 
Dodder,  133. 
Dodecatheon,  125. 
Dogbane  Family,  130. 
Dog  Fennel,  182. 
Dog-tooth  Violet,  29. 
Dogwood  Family,  119. 
Douglas  Spruce,  17. 
Downingia,  161. 
Drooping  Live  Oak,  45. 
Drops  of  Gold,  34. 
Dutchman's  Pipe,  47. 
Dutchman's  Pipe  Family,  46. 

Echeveria,  74. 
Echinocactus,  115. 
Echinocystis,  158. 
Elder,  157. 
Ellisia,  134. 
Emmenanthe,  136. 
Encelia,  176. 
Encino,  45. 

Engelmann  Spruce,  17. 
Epilobium,  111. 


INDEX 


191 


Epipactis,  39. 
Eremocarpus,  100. 
Ericaceae,  120. 
Erigeron,  171. 
Eriodictyon,  136. 
Eriogonum,  47. 
Eriophyllum,  180. 
Erodium,  96. 
Erysimum,  69. 
Erythrsea,  128. 
Erythronium,  29. 
Eschscholtzia,  64. 
Escobita,  150. 
Eucalyptus,  110. 
Eucharidium,  114. 
Eunanus,  152. 
Eupatoriacese,  162,  167. 
Euphorbia,  99. 
Euphorbiacese,  99. 
Evening  Primrose,  112. 
Evening  Primrose  Family,  110. 
Evening  Snow,  131. 
Evergreen  White  Oak,  44. 
Everlasting,  173. 

Fairy  Bells,  34. 

False  Solomon's  Seal,  34. 

Farewell  to  Spring,  113. 

Fatsia,  117. 

Ficoidese,  116. 

Fiddle-neck,  137. 

Fig  Marigold  Family,  116. 

Figwort  Family,  146. 

Filaree,  96. 

Fir,  16. 

Firecracker  Flower,  26. 

Fireweed,  111. 

Five-finger,  85. 

Flaming  Poppy,  66. 

Flax  Family,  98. 

Fleabane,  172,  183. 


Fleur  de  Lis,  37. 
Flower  de  Luce,  37. 
Flowering  Ash,  128. 
Flowering  Currant,  78. 
Flowering  Willow,  172. 
Footsteps  of  Spring,  112. 
Forget-me-not,  138. 
Four-o'clock,  52. 
Four-o'clock  Family,  51. 
Fragaria,  86. 
Frankeniaceae,  108. 
Franseria,  174. 
Fraxinus,  128. 
Fremontia,  107. 
Fringed  Cups,  76. 
Fringed  Gilia,  131. 
Fritillaria,  28. 

Fuchsia-flowered  Gooseberry,  78. 
Fumariaceae,  66. 

Galium,  155. 
Garrya,  120. 
Garryaceae,  120. 
Gaultheria,  123. 
Gentianaceae,  128. 
Gentian  Family,  128. 
Geraniacese,  95. 
Geranium  Family,  95. 
Geum,  84. 
Gilia,  130. 
Ginger  Pine,  14. 
Ginseng,  117. 
Ginseng  Family,  116. 
Githopsis,  159. 
Gnaphalium,  173. 
Godetia,  113. 
Golden  Aster,  169. 
Golden  Bells,  30. 
Golden  Bloomeria,  25. 
Golden  Cup  Oak,  45. 
Golden  Ear-drops,  67. 


192 


KEY   AND   FLORA 


Golden-eyed  Grass,  38. 
Golden  Fields,  179. 
Golden-leaved  Chinquapin,  46. 
Golden  Pea,  89. 
Golden  Prince's  Plume,  73. 
Golden-rod,  170. 
Golden  Stars,  25. 
Golden  Tulips,  32. 
Gomphocarpus,  129. 
Gooseberry,  78. 
Gourd  Family,  158. 
Graminese,  21. 
Grass  Family,  21. 
Grass  Lilies,  27. 
Grass  Nuts,  26. 
Greasewood,  84,  141. 
Green-stemmed  Filaree,  97. 
Grindelia,  168. 
Ground  Lily,  26. 
Groundsel,  184. 
Gum  Plant,  168. 
Gymnosperms,  13. 

Habenaria,  39. 
Hairy  Bell,  30. 
Hardback,  82. 
Harebell,  160. 
Harebell  Family,  159. 
Hazelnut,  46. 
Heal-all,  143. 
Heart's-ease,  109. 
Heather  Family,  120. 
Hedge  Nettle,  143. 
Helenioideae,  163,  179. 
Helenium,  181. 
Helianthemum,  108. 
Helianthoidese,  162,  175. 
Helianthus,  176. 
Heliotrope,  137. 
Heliotropium,  137. 
Hemizonia,  178. 


Hemlock  Spruce,  17. 
Heracleum,  118. 
Hesperochiron,  136. 
Hesperocordum,  27. 
Heteromeles,  88. 
Heuchera,  77. 
Hog's  Potato,  34. 
Holodiscus,  83. 
Hookera,  26. 

Honeysuckle  Family,  156. 
Horehound,  143. 
Hosackia,  92. 
Hound's  Tongue,  138. 
Houttuynia,  40. 
Huckleberry,  120. 
Humboldt's  Lily,  28. 
Hydrophyllaceae,  133. 
Hydrophyllum,  133. 
Hypericacese,  107. 
Hypericum,  107. 
Hypochseris,  164. 

Ice  Plant,  116. 
Illecebracese,  57. 
Incense  Cedar,  15. 
Indian  Hemp,  130. 
Indian  Lemonade,  101. 
Indian  Melon,  115. 
Indian  Paint-brush,  149. 
Indian  Warrior,  151. 
Inuloidese,  162,  172. 
Iridaceae,  37. 
Iris  Family,  37. 
Isomeris,  73. 
Islay,  81. 
Ithuriel's  Spear,  27. 

Jewel-flowers,  72. 
Jointed  Cactus,  116. 
Jointweed,  49. 
Jonquil,  36-37. 


INDEX 


193 


Judas-tree,  95. 
June  Berry,  87. 
Juniper,  13. 
Juniperus,  13. 

Kelloggia,  154. 
Kellogg's  Oak,  45. 
Kinnikinick,  121. 
Knob-cone  Pine,  20. 
Kunzia,  83. 

Labiatse,  139. 
Labiatiflorae,  162,  167. 
Labrador  Tea,  124. 
Lace  Pod,  67. 
Ladies'  Tresses,  39. 
Lady's  Slipper,  39. 
Lamb's  Quarter,  50. 
Large-leaved  Maple,  102. 
Larkspur,  61. 
Lasthenia,  179. 
Lathyrus,  94. 
Lauraceae,  63. 
Laurel  Family,  63. 
Lavatera,  105. 
Layia,  179. 
Ledum,  124. 
Leguminosae,  89. 
Leopard  Lily,  28. 
Lepidium,  68. 
Lepigonum,  57. 
Leptosyne,  177. 
Lessingia,  168. 
Lewisia,  53. 
Libocedrus,  15. 
Liguliflorse,  162,  164. 
Lilac  Tulip,  32. 
Liliaceae,  23. 
Lilium,  27. 
Lily  Family,  23. 
Limnanthes,  97. 


Linaceae,  98. 
Linanthus,  131. 
Linum,  98. 
Live  Oak,  45. 
Lizard-leaf,  180. 
Loasacese,  115. 
Lobeliaceae,  160. 
Lobelia  Family,  160. 
Loco-weed,  94. 
Lodge-pole  Pine,  19. 
Lonicera,  156. 
Lotus,  92. 
Love  Vine,  133. 
Lucerne,  92. 
Lupine,  90. 
Lupinus,  90. 
Lysichiton,  23. 

Madder  Family,  154. 
Madia,  177. 
Madrone,  121. 
Madrono,  121. 
Mahala  Mats,  105. 
Mahonia,  63. 
Malacothrix,  165. 
Mallow  Family,  105. 
Malus,  88. 
Malvaceae,  105. 
Malvastrum,  106. 
Mamillaria,  115. 
Mammoth  Sequoia,  16. 
Manzanilla,  182. 
Manzanita,  121. 
Maple,  102. 
Mariposa  Lily,  30. 
Marrubium,  143. 
Marsh  Fleabane,  172. 
Matilija  Poppy,  66. 
Matricaria,  182. 
Mayweed,  182. 
Meadow  Foam,  97. 


194 


KEY  AND   FLORA 


Meadow-rue,  59. 
Meadow-sweet,  83. 
Meconopsis,  66. 
Medicago,  92. 
Megarrhiza,  158. 
Melilotus,  91. 
Mentha,  139. 
Mentzelia,  115. 
Mertensia,  138. 
Mesembryanthemum,  116. 
Mexican  Poppy,  65. 
Micrampelis,  158. 
Micromeria,  140. 
Microseris,  165. 
Milfoil,  182. 
Milkmaids,  71. 
Milk  Thistle,  185. 
Milkweed,  99. 
Milkweed  Family,  129. 
Mimosese,  95. 
Mimulus,  151. 
Miner's  Lettuce,  53. 
Mint  Family,  139. 
Mirabilis,  52. 
Mission  Bells,  28. 
Mock  Orange,  79. 
Monardella,  139. 
Monkey  Flower,  151. 
Monkshood,  61. 
Monocotyledonous  Plants,  20. 
Monolopia,  180. 
Monterey  Cypress,  14. 
Monterey  Pine,  20. 
Montia,  53. 

Morning-glory  Family,  132. 
Mountain  Ash,  89. 
Mountain  Cypress,  14. 
Mountain  Mahogany,  83. 
Mountain  Misery,  85. 
Mouse-ear  Chickweed,  55. 
Mouse-ears,  31. 


Mugwort,  183. 
Muilla,  25. 
Musk  Plant,  152. 
Mustard,  69. 
Mustard  Family,  67. 
Myricacese,  40. 
Myrtacese,  110. 
Myrtle  Family,  110. 

Narcissus,  37. 

Nasturtium,  70. 

Navarretia,  131. 

Needle  Bush,  90. 

Negundo,  103.. 

Neillia,  82. 

Nemophila,  134. 

Nicotiana,  146. 

Nigger  Babies,  118. 

Nightshade  Family,  14.5. 

Ninebark,  82. 

Nodding  Evening  Primrose,  112. 

Nut  Pine,  20. 

Nuttallia,  81. 

Nyctaginaceae,  51. 

Oak  Family,  44. 
(Enothera,  112. 
Old  Man  of  Spring,  184. 
Oleacese,  127. 
Onagracese,  111. 
Opuntia,  116. 
Orchidacese,  39. 
Orchis  Family,  39. 
Oregon  Ash,  128. 
Oregon  Cedar,  14. 
Oregon  Grape,  62. 
Oregon  Pine,  18. 
Oregon  Sweet  Clover,  63. 
Orobanchacese,  153. 
Orthocarpus,  150. 


INDEX 


195 


Osinaronia,  81. 
Oso  Berry,  81. 
Owl's  Clover,  150. 
Oxalis,  97. 
Oyster  Plant,  164. 

P&eonia,  62. 
Paeony,  62. 
Pansy,  109. 
Papaveraceae,  64. 
Papilionacese,  89. 
Parsley  Family,  117. 
Pattern's  Spruce,  17. 
Pea  Family,  89. 
Pear,  88. 

Pearly  Everlasting,  173. 
Pea  Vine,  94. 
Pedicularis,  151. 
Pentacaena,  58. 
Pentstemon,  148. 
Pepper  Grass,  68. 
Pepper-root,  71. 
Pepper  Tree,  101. 
Perezia,  167. 
Phacelia,  135. 
Philadelphia,  79. 
Phlox  Family,  130. 
Photinia,  88. 
Physocarpus,  82. 
Picea,  16. 
Pickeringia,  90. 
Pigweed,  51. 
Pigweed  Family,  49. 
Pimpernel,  126. 
Pine,  18. 
Pine  Family,  13. 
Pink  Family,  55. 
Pinus,  18. 
Piperacese,  39. 
Plantaginaceae,  153. 
Plantago,  153. 


Plantain  Family,  153. 
Platyspernmm,  70. 
Platystemon,  65. 
Platystigma,  65. 
Pluchea,  172. 
Plum,  81. 

Plumbaginacese,  127. 
Poison  Oak  Family,  101. 
Polemoniaceae,  130. 
Polygalaceae,  98.    : 
Polygala  Family,  98. 
Polygonacese,  47. 
Polygonum,  49. 
Pomeae,  87. 

Poor  Man's  Barometer,  126. 
Popcorn  Flower,  150. 
Poplar,  42. 
Poppy  Family,  64. 
Populus,  42. 
Port  Orford  Cedar,  14. 
Portulaca,  53. 
Portulacaceae,  52. 
Portulaca  Family,  52. 
Post  Oak,  45. 
Potato,  145. 
Potentilla,  85. 
Prairie  Pointers,  125. 
Prickly  Poppy,  65. 
Primrose  Family,  125. 
Primulaceae,  125. 
Prince's  Pine,  124. 
Prosartes,  34. 
Prunus,  81. 
Pseudotsuga,  17. 
Psoralea,  93. 
Pulse  Family,  89. 
Purple  Sanicle,  118. 
Purshia,  83. 
Purslane,  53. 
Pusley,  53. 
Pussy-paws,  54. 


196 


KEY   AND   FLORA 


Pyrola,  125. 
Pyrus,  88. 

Quaking  Asp,  42. 
Quercus,  44. 
Quinine  Bush,  120. 

Rabbit-brush,  170. 
Radish,  69. 
Rafinesquia,  165. 
Rammculacese,  58. 
Ranunculus,  59. 
Raphanus,  69. 
Raspberry,  86. 
Rattlesnake  Weed,  119. 
Rattleweed,  94. 
Red-bud,  95. 
Red  Columbine,  60. 
Red  Fir,  18. 

Red  Monkey  Flower,  161. 
Red-stemmed  Filaree,  96. 
Redwood,  15. 
Redwood  Rose,  87. 
Rhamnacese,  103. 
Rhamnus,  103. 
Rhododendron,  123. 
Rhus,  101. 
Ribes,  78. 
Rice  Roots,  28. 
Roble,  44. 
Rock  Cress,  71. 
Rockrose  Family,  108. 
Romero,  144. 
Romneya,  66. 
Rosa,  87. 
Rosaceae,  80. 
Rose,  87. 
Roseae,  82. 
Rose-bay,  123. 
Rose  Family,  80. 
Rose  Mallow,  106. 


Rosy  Bells,  31. 
Rowan,  89. 
Rubiacese,  154. 
Rubus,  86. 
Rumex,  48. 

Sage,  140. 

Sagebrush,  182. 

St.  John's-wort  Family,  107. 

Salal,  123. 

Salicaceae,  40. 

Salix,  41. 

Salmon-berry,  86. 

Salmon-color  Gilia,  131. 

Salsafy,  164. 

Salt-marsh  Dodder,  133. 

Salty  Sage,  50. 

Salvia,  140. 

Sambucus,  157. 

Sand  Mat,  58. 

Sandwort,  56. 

Sanicle,  118. 

Sanicula,  118. 

Sapindacese,  102. 

Satin  Bell,  30. 

Saxifraga,  75. 

Saxifragacese,  75. 

Saxifrage  Family ,.75. 

Scarlet  Gilia,  132. 

Scotch  Caps,  86. 

Scrophularia,  147. 

Scrophulariaceae,  146. 

Scutellaria,  142. 

Sea  Lavender,  127. 

Sea  Pink  Family,  127. 

Seaside  Daisy,  171. 

Seaside  Morning-glory,  132. 

Sea  Verbena,  52. 

Sedge  Family,  22. 

Sedum,  74. 

Self-heal,  142. 


INDEX 


197 


Senebiera,  68. 
Senecio,  184. 
Senecionidese,  163,  183. 
Sequoia,  15. 
Service  Berry,  87. 
Shepherd's  Purse,  69. 
Shooting  Stars,  125. 
Sidalcea,  106. 
Silene,  55. 

Silk-tassel  Bush  Family,  120. 
Silkweed,  129. 
Silvery  Cinquefoil,  85. 
Silybum,  185. 
Sisyrinchium,  38. 
Skullcap,  142. 
Skunk  Cabbage,  23. 
Skunkweed,  131. 
Slippery  Elm,  107. 
Small  Sugar  Pine,  18. 
Small  Tiger  Lily,  28. 
Smartweed,  49. 
Smilacina,  34. 
Snakeroot,  118. 
Sneezeweed,  181. 
Snowberry,  156. 
Snow-bush,  104. 
Soap  Plant,  33,  50. 
Soapweed,  30. 
Solanacese,  145. 
Solanum,  145. 
Solidago,  170. 
Sonchus,  166. 
Sorbus,  89. 
Sorrel,  48. 
Sour  Grass,  48. 
Sow  Thistle,  166. 
Spanish  Bayonet,  30. 
Speedwell,  147. 
Spergula,  57. 
Spergularia,  57. 
Sphacele,  140. 


Spice  Wood,  64. 
Spikenard,  117. 
Spiny  Chaparral,  90. 
Spiraea,  82. 
Spiranthes,  39. 
Spraguea,  54. 
Spruce,  16. 
Spurge,  99. 
Spurge  Family,  99. 
Squaw  Bush,  101. 
Squaw-carpets,  105. 
Stachys,  143. 
Stanfordia,  72. 
Stanleya,  73. 
Star-eyed  Grass,  38. 
Star-flower,  126. 
Star  Thistle,  185. 
Statice,  127. 
Steironema,  126. 
Stellaria,  56. 
Stephanomeria,  165. 
Stonecrop,  74. 
Stonecrop  Family,  74. 
Strawberry,  86. 
Streptanthus,  72. 
Streptopus,  35. 
Strophilirion,  26. 
Sugar  Pine,  18. 
Sumac,  100. 
Sun  Cups,  112. 
Sun  Dial,  90. 
Sunflower,  176. 
Sunshine,  179. 
Sweet  Clover,  91. 
Sweet-in-death,  63. 
Sweet  Shrub  Family,  80. 
Symphoricarpos,  156. 
Syringa,  79. 

Tanbark  Oak,  45. 
Taraxacum,  166. 


198 


KEY  AND   FLORA 


Tarweed,  85,  177. 
Tellima,  76. 
Thalictrum,  59. 
Thelypodium,  73. 
Therraopsis,  89. 
Thimbleberry,  86. 
Thistle,  185. 
Thistle  Poppy,  65. 
Thistle  Sage,  141. 
Thorn-apple,  88,  145. 
Thrift,  127. 
Thuya,  14. 
Thysanocarpus,  67. 
Tiarella,  77. 
Tideland  Spruce,  16. 
Tidy-tips,  179. 
Tiger  Lily,  28. 
Tissa,  57. 
Tobacco,  146. 
Tocalote,  186. 
Tolmiea,  77. 
Tooth  wort,  71. 
Tower  Mustard,  71. 
Toyon,  88. 
Tragopogon,  164. 
Tree  Mallow,  105. 
Tree  Poppy,  64. 
Tree  Tobacco,  146. 
Trichostema,  144. 
Trientalis,  126. 
Trifolium,  91. 
Trillium,  36. 
Triteleia,  27. 
Troximon,  166. 
Tsuga,  17. 

Tubuliflorae,  162,  167. 
Tumbleweed,  51. 
Turkey  Mullein,  100. 
Turkish  Rugging,  48. 
Twelve  Gods,  125. 
Twin-berry,  156. 


Twining  Hyacinth,  26. 
Twisted  Stalk,  35. 

Umbelliferse,  117. 
Umbellularia,  63. 

Vaccinium,  120. 
Valeriana,  159. 
Valerianacese,  158. 
Valerianella,  159. 
Valerian  Family,  158. 
Valley  Oak,  44. 
Veronica,  147. 
Vetch,  94. 
Vicia,  94. 
Vine  Maple,  102. 
Viola,  109. 
Violacese,  109. 
Violet  Family,  109. 
Virgin's  Bower,  58. 

Wake  Robin,  36. 
Waldmeister,  155. 
Wallflower,  69. 
Wart  Cress,  68. 
Washington  Lily,  27. 
Water  Cress,  70. 
Water  Holly,  63. 
Waterleaf,  133. 
Wax-myrtle  Family,  40. 
Weeping  Oak,  44. 
Western  Chinquapin,  45. 
Western  Dandelion,  166. 
Whipplea,  80. 
Whispering  Bells,  136. 
White  Evening  Primrose,  112. 
White  Fir,  16. 
White  Mustard,  69. 
White  Oak,  44. 
White  Sage,  141. 


INDEX 


199 


White  Spruce,  17. 
Whiteweed,  182. 
Wild  Cabbage,  72. 
Wild  Cypress,  132. 
Wild  Fuchsia,  111. 
Wild  Ginger,  46. 
Wild  Hyacinth,  25,  26. 
Wild  Onion,  24. 
Wild  Pea,  94. 
Willow,  41. 
Willow  Family,  40. 
Willow  Herb,  111. 
Willow-leaved  Dock,  48. 
Windflower,  59. 
Wintercress,  70. 
Wintergreen,  125. 
Wood  Sorrel,  97. 
Wood  Strawberry,  86. 
Woolly  Breeches,  137. 
Wormseed,  50. 
Wormwood,  182. 
Wyethia,  175. 


Xanthium,  174. 
Xylothermia,  90. 

Yarrow,  182. 

Yellow  Evening  Primrose,  112. 

Yellow  Lessingia,  168. 

Yellow  Mats,  118. 

Yellow  Pine,  18. 

Yellow  Rocket,  70. 

Yellow  Sorrel,  98. 

Yellow  Star  Tulips,  31. 

Yerba  Buena,  140. 

Yerba  de  la  Vibora,  119. 

Yerba  del  Pasmo,  84. 

Yerba  del  Pescado,  100. 

Yerba  Mansa,  40. 

Yerba  Mansa  Family,  39. 

Yerba  Rheuma  Family,  108. 

Yerba  Santa,  136. 

Yucca,  30. 

Zauschneria,  111. 
Zygadenus,  33. 


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Gage's  Elements  of  Physics.   (Revised  Edition) 1.12  1.20 

Gage's  Physical  Experiments 35  .45 

Gage's  Physical  Laboratory  Manual  and  Notebook 35  .45 

Gage's  Introduction  to  Physical  Science i.oo  i.io 

Gage's  Introduction  to  Physical  Science.     (Revised)       .....     i.oo  i.io 

Hastings  and  Beach's  General  Physics 2.75  2.95 

Higgins'  Lessons  in  Physics 90  i.oo 

Lincoln's  Hygienic  Physiology 80  .90 

Meier's  Herbarium  and  Plant  Description.     With  directions  for  col- 
lecting, pressing,  and  mounting  specimens 60  .70 

Moore's  Laboratory  Directions  for  Beginners  in  Bacteriology      .     .     i.oo  1.05 

Nichols,  Smith,  and  Turton's  Manual  of  Experimental  Physics  .     .       .90  i.oo 

35 
35 


Pratt's  Invertebrate  Zoology 1.25 

Sabine's  Laboratory  Course  in  Physical  Measurements      ....  1.25 

Sellers'  Elementary  Treatise  on  Qualitative  Chemical  Analysis      .  .75 

Snyder  and  Palmer's  One  Thousand  Problems  in  Physics      ...  .50 

Stone's  Experimental  Physics i.oo 

Thorp's  Inorganic  Chemical  Preparations 1.50 

Upton's  Star  Atlas 2.00 

Ward's  Practical  Exercises  in  Elementary  Meteorology    ....  1.12 


•55 
.10 
.60 

•!5 

Wentworth  and  Hill's  Text-Book  of  Physics     ...".....     1.15  1.25 

Wentworth  and  Hill's  Laboratory  Exercises  in  Elementary  Physics       .25  .27 

White's  Elementary  Chemistry i.oo  i.io 

Williams'  Chemical  Experiments 50  .60 

Williams'  Chemical  Exercises 30  .35 

Williams' Elements  of  Chemistry i.io  1.20 

Williams' Introduction  to  Chemical  Science .       .80  .90 

Williams'  Laboratory  Manual  of  Inorganic  Chemistry 30  .35 

Williams'  Laboratory  Manual  of  General  Chemistry 25  .30 

Young's  Elements  of  Astronomy 1.60  1.75 

Young's  General  Astronomy 2.75  3.00 

Young's  Lessons  in  Astronomy.     (Revised  Edition) 1.25  1.40 

Young's  Manual  of  Astronomy 2.25  245 


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BLAISDELL'S    PHYSIOLOGIES 

By  ALBERT  F.   BLAISDELL,  M.D. 


CHILD'S  BOOK  OF  HEALTH.  In  easy  lessons  for  schools.  Cloth.  136 
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and  preservation  of  the  health.  The  books  present  in  clear  and 
simple  language  the  latest  and  most  trustworthy  facts  on  physiology 
and  hygiene.  Important  facts  are  illustrated  by  a  series  of  simple 
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on  the  subject  of  physical  culture. 

The  effects  of  alcoholic  drinks,  tobacco,  and  other  narcotics 
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TEXT-BOOKS  ON  ASTRONOMY 

By  CHARLES  A.  YOUNG 

Professor  of  Astronomy,  in  Princeton  University 

Lessons  in  Astronomy.  (Revised  Edition)  Including  Star  Maps. 
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Elements  of  Astronomy.  With  a  Uranography.  464  +  42  pages 
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The  Lessons  in  Astronomy  was  prepared  for  schools  that  desire 
a  brief  course  free  from  mathematics.  The  book  is  fully  down 
to  date,  and  several  beautiful  plates  of  astronomical  objects  and 
instruments  have  been  inserted  in  the  revised  edition. 

The  Elements  of  Astronomy  is  a  text-book  for  advanced 
high  schools,  seminaries,  and  brief  courses  in  colleges  generally. 
Special  attention  has  been  paid  to  making  all  statements  accurate. 

The  Manual  of  Astronomy  is  a  new  work  prepared  in  response 
to  a  pressing  demand  for  a  class-room  text-book  intermediate 
between  the  author's  "  General  Astronomy  "  and  his  «  Elements  of 
Astronomy."  It  is  largely  made  up  of  material  drawn  from  the 
earlier  books,  but  rearranged,  rewritten  when  necessary,  and 
added  to  in  order  to  suit  it  to  its  purpose  and  to  bring  it  thor- 
oughly down  to  date. 

The  eminence  of  Professor  Young  as  an  original  investigator  in 
astronomy,  a  lecturer  and  writer  on  the  subject,  and  an  instructor  in 
college  classes,  led  the  publishers  to  present  the  General  Astronomy 
with  the  highest  confidence ;  and  this  confidence  has  been  fully 
justified  by  the  event.  It  is  conceded  to  be  the  best  astronomical 
text-book  of  its  grade. 

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LESSONS  IN   PHYSICS 

'     By  LOTHROP  D.   HIGGINS 

Instructor  in   Physics  in  the  Morgan   School,   Clinton,   Conn.      I2mo.     Cloth. 
379  pages.      Illustrated.      List  price,    90  cents;   mailing  price,   $1.00. 


HIGGINS'  "Lessons  in  Physics"  provides  a  thorough 
course  in  physics  for  schools  which  offer  little  or 
no  laboratory  work.  Principles  are  explained  by 
references  to  common  or  familiar  phenomena  rather  than  to 
set  laboratory  experiments.  In  fact,  throughout  the  work  the 
central  aim  has  been  to  give  the  student  an  intimate  knowl- 
edge of  the  physical  manifestations  that  are  most  commonly 
met  in  our  daily  experience.  Commercial  and  industrial  uses- 
of  the  various  principles  are  mentioned  and  discussed  in 
connection  with  the  principles  themselves. 

The  author  has  taken  great  pains  to  secure  simplicity  and 
clearness  of  expression;  facts  are  explained  so  that  the  pupil 
is  led  to  think  them  through  and  thus  to  fix  them  in  mind. 
In  arranging  the  material,  attention  is  paid  to  developing  a 
logical  succession  of  ideas  rather  than  to  collecting  a  mass 
of  facts  and  theories.  Technical  words  are  in  most  cases 
defined  when  they  first  appear.  For  words  which  are  not 
thus  explained  a  glossary  is  appended  to  the  text. 

As  a  whole,  this  is  a  text-book  designed  to  present  with- 
out required  laboratory  work  a  comprehensive  view  of  the 
subject  of  physics  in  a  manner  which  will  be  interesting,  and 
at  the  same  time  strictly  accurate. 

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Foundations  of  botany 


